Caring for your new Lawn

Lawn care

After all the what-to-do’s and the what-not-to-do’s have been out- lined in this section, it is conceivable that a reader might become overwhelmed with the amount of work involved in caring for a lawn. This conclusion would be unfortunate, since lawn care is entirely up to the lawn owner.

We have presented the plan to grow the perfect lawn, but we also realize that the perfect lawn is not the goal of all people. We provide this information to answer the many questions concerning lawn care. We feel it is important to give you an understanding of how certain aspects of lawn care are interrelated, and how they affect a lawn’s appearance.

Level of maintenance

When it comes right down to it, any lawn looks better than having no lawn at all. Take a walk through your neighborhood and observe some of the lawns that look appealing. Notice at the same time how the lawn complements the house. Look closely; is it weed free? … are there bad spots? We doubt you’ll find many perfect lawns, but lawns aren’t required to be perfect, only to be appealing and functional, The degree of lawn maintenance depends a good deal on convenience and the amount of time one has to spend on lawn care. When you fertilize, mow, or take care of weeds, probably depends on when you have the time. These tasks do not have to reduce the pleasure derived from caring for a lawn. Who can say who gets more enjoyment;” the lawn connoisseur or the Saturday morning mower”?

Have a balanced program

Although the different aspects of taking care of a lawn can be broken down conveniently into chapters and sub-chapters, actual lawn care is not so precise. A lawn that is properly watered and fertilized will have fewer problems with weeds and disease. On the other hand, it will also have to be mowed more often. Regular mowing is a good method of weed control. The key to success,no matter what your maintenance approach, is to have a balanced program of lawn care. If you mow less, water and fertilize less. If you enjoy getting outdoors and watering, balance this with extra fertilizing. By understanding all of the needs of your lawn, you will be able to have the lawn you desire. More importantly, you will see that lawn care can be simplified and enjoyable. Al little exercise on a sunny afternoon, the feel and fragrance of a fresh cut lawn – these are the pleasures of lawn care.


Not withstanding pages of magazine cartoons, it’s our feeling that most people reading this content don’t really mind mowing their lawns. Mowing is a good way to stretch muscles and get out among the neighbors. It’s also difficult lo imagine anything that smells or feels better than a freshly cut lawn,

Many people who want a handsome lawn don’t realize just how important the job of mowing is. A lawn that is mowed when necessary and at the right height resists invasions of weeds, insects, and disease, and has a more lush, healthy look. Mowing infrequently, which often results in removal of too much grass at one time, will eventually produce a lawn with a thin, spotty, or burned out appearance.

How often to mow

How often your lawn needs mowing depends primarily on three things: the kind of grass, how often and how much you water and fertilize, and of greatest importance, the time of year. The best rule of thumb is this: Mow when the grass grows to one-fourth to one-third taller than its recommended mowing height. In other words, if your lawn’s mowing height is 2 inches, mow when it’s about 3 inches high, thus removing one third of the height of the grass blade. Of course, this may not fit your natural. once-a-week habit or allow for vacations. In some cases, it means frequent mowing. For instance, well fertilized improved bermuda grass in mid-summer may need mowing every two or three days.

The penalty for not following the rule is a stiff one. By letting grass grow too high and then cutting away half or more at once, you expose stems that have been shaded and are not adapted to strong sunlight. Grass leaves may be burned by the sun and turn brown. Mowing too high results in deterioration of green leaf tissue at lower levels. More importantly, roots are severely shocked by a heavy mowing and may need several weeks to recover. Research has shown a direct relationship between height of cut and depth of roots. Roots of grasses properly mowed at correct heights will grow deeper. Deep roots are an important advantage and make lawn care many times easier.

The time of year also affects the frequency of mowing. The warm-season grasses commonly used in much of the south barely grow at all in the winter and slowly in the spring and fall. Mowing is infrequent during these times. But during the high temperatures of summer, growth will be more vigorous and mowing will be more frequent. How much water and fertilizer you apply affects the growth rate of lawns, and consequently, the frequency of mowing. Obviously, lawns maintained at high levels of growth-stimulating fertilizer will require more frequent mowing. For example, golf course greens are usually mowed several times per week, sometimes daily. More labor is one price of the luxurious lawn.

The right height

The proper mowing height depends primarily on the kind of grass. Generally, grasses grow either horizontally or upright. For instance, bemuda and bentgrass spread widely with lateral growing stems called stolons. These stolons parallel the ground as well as the cut of the mower, so are not normally mowed off. Unless grasses like these are kept mowed low, preferably with a heavy reel-type mower, they will in time build-up prodigious amounts of thatch.

Think of it this way. “X” amount of leaf surface is necessary to keep the grass plant healthy and growing. If that leaf surface is spread out low, over a wide area, the lawn can be mowed close to the ground without reducing the necessary leaf surface.

Vertically growing grasses cannot be mowed excessively low since the leaf surface area isn’t enough to support the plant. Tall fescue, St,Augustine, bahia, and common Kentucky bluegrass fit Into this category. Below a certain height (1 1/2 or 2 inches from the ground), too little leaf surface remains to maintain a good turf.

Mowing too low probably ruins more Kentucky bluegrass lawns than any other practice. This is especially true in transitional areas where adaptation is marginal. Cut high, Kentucky bluegrass is much more disease resistant and can successfully compete with weeds and insects. The tall growth also shades the soil, keeping temperatures lower for cool-loving roots.

Exceptions are some of the new varieties of bluegrass, which are essentially dwarfs. They are more compact and have more leaf surface in less area. ‘Fylking’ and ‘Nugget’ are two varieties In this category. These dwarfs will tolerate much lower mowing (as low as 3/4 inch) than common Kentucky bluegrass.

The University of Georgia points out that the height of a cut can have a big influence on winter survival. Centipede grass cut at 1 ½ inches Instead of 2 1/2 inches has a much better chance of surviving a winter without damage. St. Augustine grass is just the opposite; cutting it higher in the fall helps winter survival. This is also true for bermuda, and zoysia grass, although neither is as susceptible to cold as St. Augustine grass.

Where shade is a problem, mow another 1/2 inch higher. This increases the light-trapping power for photosynthesis of the lawn.

The clippings removal question

Some experts say clippings should always be removed, others say it’s not necessary. Here’s the way the facts sorted out for us. Latest research has shown that clippings of cool-season grasses left on the lawn do not cause or contribute to thatch. It’s the woody, slow to decompose stems, rhizomes, and stolons below the grass blades that contribute most to thatch build-up. Because they are more stiff and slow to breakdown. How much the clippings of other arm-season grasses contribute to thatch is still an open question.

Clippings return nutrients to the lawn. It’s difficult to measure, but some estimates suggest that as much as one third of a lawns nitrogen requirement can be supplied by decaying grass clippings.

There are two reasons not to leave clippings on your lawn, First of all, they can be unsightly, clippings are removed from many a high quality, intensely maintained lawn for just this reason, Secondly, if your lawn is not mowed frequently enough, too much grass will be cut off at one time. Instead of sifting down and decomposing, the clippings can mat on top and suffocate the grass underneath.

At the time of year when your lawn is growing vigorously, clippings will probably have to be removed. With very large lawns, removal of clippings becomes impractical, as is the case with parks and golf courses.

Mowing new lawns

Newly seeded lawns are more delicate than established ones. That’s why you have to he more careful mowing them. The soil is very soft and the grass plants usually aren’t deeply rooted by the time of the first mowing. On the other hand, mowing young lawns, especially those planted vegatatively, encourages spreading, thus promoting a thicker lawn. Basically, use common sense and apply the
same principles of proper mowing of any lawn. You’ll probably want to let the new grass grow a little beyond the normal recommended cutting height. Even then, mow it very lightly, removing less than a third of the total height. If you can, use a mower that’s not too heavy, especially if the soil is still soft. A lightweight rotary or a sharp push-reel mower is your best bet. If the soil remains too soft or if the new grass is too loosely knit to mow without damage, wait. Let the lawn continue to grow, and then cut it gradually until it is down to the proper height (1/2 to 3/4 inch reduction every second mowing until height is reached).

Lawn mowing miscellany

-Don’t cut wet grass. Why? It can cause uneven mowing, the clippings are messy, and they can mat and suffocate the grass.
-Pick up stones and sticks before mowing.
-Alternate mowing patterns. Mowing the same direction every time tends to compact the soil and causes wear patterns
-For an attractive “checkered” finish to a lawn, mow it twice, traveling in opposite directions.
-Reel mowers sometimes cause a ribbed pattern leaving the lawn with a washboard look. This is caused by a mower moving forward too fast for the height of cut. In other words, it’s possible to push a mower faster than the blades can make regular cuts.
-Check blade height with a ruler extended from the cutting edge to a flat surface such as a sidewalk or driveway.
-Sharp turns with a mower can cause uneven cutting. Make wide turns or use sidewalks and driveways, but be aware of rocks or debris on pavement areas.
– If the ground is uneven from settling of the soil in some areas, scalping may result as you go over the high spots.
-Reel mowers are preferred for fine lawns. They cut the grass cleanly, with a scissor like action and smoothly follow surface contours. They perform poorly on tall grasses and lawns with high, wiry seed heads,
-The blades of rotary mowers are easy to sharpen at home. Only a small portion at the end of the blade actually cuts the grass. Sharpen the edge with a file or grindstone, making sure to even out any rough spots. Check balance before remounting.

Flail (also known as hammer knife) and sickle bar are less common types of mowers. Flail mowers use floppy, T-shaped blades revolving on a horizontal shaft to cut grass. They are useful in maintaining rough areas such as vacant lots and the sides of highways. Sickle bar mowers are used for cutting very high grass and weeds. It’s the same sort of mower that farmers use to cut field oats and other hays and grains.
-Experts disagree about the safest way to mow steep inclines. Some say across, others say up and down the slope. Use common sense, and be aware of the danger a power mower represents. Check its stability and be aware that a slipping mower can injure both you and your lawn. Perhaps the best way to handle a slope is to plant a ground cover that doesn’t need mowing,
-Trees in a lawn require special protection from mower damage.

Lawn mowers

Almost every suburban homeowner has a lawn mower. The number of varieties and styles available proliferates each year. It pays to shop around to see what is available, to find the mower that fits your needs. The two most common basic mowers are the reel and the rotary. Within each basic type are variations of gas or electric power, walking or riding, push, or self-propelled. Some have bagging attachments, or catchers, Before buying a lawn mower, look it over carefully. Consider its maneuverability. Make sure the grass catcher is easy to take on and off. Check to see how easy the blades are to adjust. Ask about the safety features. These points will help you choose the right mower. Mowers can be very specialized. Some are designed to cut high weeds, others are engineered to produce the carpet like nap of a putting green. There are also the unusual types, such as the one that rides on a cushion of air, and another that cuts with spinning monofilament line.

Reel or rotary: The choice for most people is usually either a rotary mower or a reel. The rotary is by far (the most popular. It is generally lower priced, more versatile, and easier to handle and maintain than the reel type.

However, rotary mowers require greater caution in use. They need larger motors with more horsepower, they can never cut as cleanly as a sharp, properly adjusted reel, and few can mow lower than 1 inch,

Reel mowers are available in manual (push) models, or powered with gasoline or electric engines. They cut with a scissor action, which produces the cleanest cut. They conform better to land contours than rotaries, but are impractical on rough, uneven ground or tall-growing grass. They can be adjusted to cut very low, so are the preferred type mower to use for lawns of bermuda or bentgrass, for example.

Power reel mowers discharge clippings from the rear or the front (rear-throw, front-throw). The rear-throw type is widely available and somewhat less expensive. It was most popular before the rotary became the common choice.

Front-throw reel mowers are used primarily by professional landscape gardeners. They are usually well made and can stand constant use. The weight and power of these mowers makes them perfect for the low mowing requirements of tough bermuda or zoysia grass lawns. Height is also easier lo adjust, usually with just a lever. Some can be adjusted low enough to cut right at the soil line. Riding mowers: You will probably need a riding mower if your lawn is measured in units or multiples of acres. Be aware they are not toys – don’t let children play with them. But they are somewhat fun to drive.

Riding mowers cut with the same action as their smaller counterparts— both rotary and reel. Rotaries are the most common.

Mower maintenance

Proper care of your lawn mower will lengthen its lifetime as well as eliminate many time-consuming problems. The manufacturer’s maintenance manual for your mower is the best guide. Basically, keep the blades sharp (this is very important) and be sure the motor oil is at the proper level. Clean the mower after use with a soft spray of water. Forceful cleaning with water or air can push dirt into delicate bearings, Do not «pray water onto a hot engine, Keep gaskets and fittings tight; oil or gas dripping onto the lawn will kill the grass. II you’re storing the mow»r for winter, clean it and drain the gas tank. Come spring, change the oil, clean the spark plug, and refill the gas tank

Safety tips

Power lawn mowing equipment is so common it is taken for granted. But power mowers alone are responsible for thousands of accidents yearly. Follow the guidelines below and those of the mower manufacturer, and you’ll miss becoming an injury statistic,

Don’t disconnect manufacturer’s safety features and always keep in mind the possible dangers.

Many fingers have been lost unclogging discharge chutes of rotary mowers. Make a habit of turning off the power and disconnecting the spark plug before thinking about reaching into the clogged grass.

Don’t try to mow where the terrain is too steep or uneven, Again, many accidents have occurred on slippery, steep slopes.

Walk over a lawn area before mowing and look for rocks, toys, sprinkler heads, and other possible obstructions.

Don’t allow children to mow until they are strong and mature enough to handle the job.

The why, how, and when of fertilization

Lawn owners accept the fact that they must mow and water to be able to maintain their lawn’s health. Some may question the need for fertilizer, but they shouldn’t. Lawn grasses live in what is basic ally an unnatural environment. They are crowded together and compete with each other, as well as neighboring trees and shrubs, for water and nutrients. They are mowed regularly and their clippings often removed. Because of this competition and the unnatural demands placed on lawns, they must be fertilized. Just as a balanced diet works best for people and animals, the same is true of lawns – they need fertilizer for sustenance. Properly fertilized, the lawn will maintain good color, density, and vigor and will not easily succumb to insects, weeds, or diseases. Under fertilized, the lawn is not only less attractive, but is considerably more susceptible to environmental stress and damage.

The nutrients a lawn needs

Scientists have singled out 16 different mineral elements as essential to the growth of all plants. Some are very common, such as oxygen from air and hydrogen from water. Others, such as zincorboron, are needed in only minute amounts usually found naturally in most soils.

Nitrogen is by far the most important element needed by a lawn. It promotes rapid growth and gives lawns a healthy color. It is also the one most often in short supply. Watering flushes it from the soil and the growing plant needs a plentiful and continuous supply. Without sufficient nitrogen, growth stops and the lawn becomes pale and yellowish.

Phosphorus is the next most important element needed for healthy growth of lawn grasses. It is required lo produce strong root growth. Phosphorus stimulates early root formation, particularly essential lo the proper development of new plantings. It is not readily flushed from the soil by watering and is needed by grass in small quantities, so most balanced lawn fertilizers contain only a low percentage.

Potassium is the third element of critical importance. Like nitrogen, it is flushed out by water but at a much slower rate. It is very important to the hardiness and disease resistance of lawn grasses, and helps promote wear-ability. Potassium is needed in about the same quantity as nitrogen but soil minerals supply a considerable amount, therefore, not as much is added to fertilizers.

Calcium, sulfur and magnesium are also needed in relatively large amounts. Calcium is either present in adequate quantities in the soil or is added through periodic applications of lime. Dolomite (ordolomitic limestone) supplies magnesium as well as calcium. Most sulfur reaches a lawn through the air, water, or organic matter.

Micro nutrients are elements needed in small amounts. If your lawn does not green-up with an application of nitrogen, the problem may be a shortage of iron. This is particularly true in areas where soil pH is high. (Yellowing can also be caused from sulfur deficiency, over-watering, manganese deficiency in sandy soils, and a pH less than 5.) A soil test may help solve persistent, seemingly soil-related problems such as these.

Types of fertilizers

A little garden store shopping will reveal an abundance of lawn fertilizers. You’ll see labels proclaiming “fast- acting,” “slow-release,” “organic and so on. But if they all contain the same basic minerals, which they do, what’s the difference? Here is a description of these products.

Organic. A chemist might argue that some man-made fertilizers are technically “organic.” Here organic refers la a fertilizer derived from plant or animal waste.

The variety of organic fertilizers is endless. There are manures of all kinds – municipal sewage sludge. blood meals, and seed meals. They all share some advantages and some disadvantages. In some areas, they may be inexpensive and easy to obtain, yet the reverse is often true. Most have distinctly beneficial soil building properties.

Usually the action of organics is slow, making it difficult to make a mistake and over fertilize. This is the major difference of organic fertilizers compared to synthetic fertilizers – nutrients are slowly released. (Blood meal is an exception. It is a fast release organic, almost as fast as mineral fertilizers.)

Organics are bulkier, heavier, and more difficult to handle. They have a low percentage of nitrogen so it is necessary to apply a much greater quantity at one time. (They may also be unpleasant to the nose.)

The main disadvantage of organic fertilizers is that the timing of nutrient release is not predictable. This is because soil microbes must be actively digesting the material making the nutrients it contains available to the lawn. Because microbes are most active when the soil is warmest, much of the organic carrier’s nutrient is made available during warm weather which, as stated elsewhere, is not the best time for a lawn to receive a heavy fertilization.

Soluble synthetic: These are the most common fertilizers used on lawns today. They too have advantages and disadvantages.

The big advantage of this type of fertilizer is predictability. Because their characteristics are known precisely, you know exactly the effect they will have on the lawn. For many types of lawns this is an important feature. They are available to the lawn before the soil has thoroughly warmed in summer, they are lower in cost than organic fertilizers, and easier to handle. Less material need be applied since the percentage of nitrogen is usually high.

There may be more work required of the gardener who uses these. More applications are necessary because the effects are short term. If your lawn requires 8 pounds of actual nitrogen a year, almost that many separate applications will be necessary.

Further, there is the possibility of ‘fertilizer burn” if over applied, if the lawn is wet as you spread the fertilizer, or if the fertilizer is not thoroughly watered in after application.

The exceptions are some “weed and feed” products which are formulated with soluble fertilizers and are designed for use on wet grass (when temperatures are moderate- under 85°.

Slow release: To some extent these fertilizers combine the characteristics of the organics and soluble synthetics. Usually they have a high percentage of nitrogen so handling large quantities of material is not necessary. But the possibility of fertilizer burn is highly reduced since the nitrogen does not become available to the plant all at once.

There are a variety of types,but most are categorized on a fertilizer bag under the heading “W.I.N”, meaning water insoluble nitrogen. Many of the commonly available lawn fertilizers are actually a combination of soluble nitrogen and W.I.N. nitrogen. Slow release fertilizers are favored by many lawn-growers because they make heavier applications of nitrogen possible, hence fewer applications are necessary. However, they don’t provide a quick green-up. You will not have the degree of control of greening response that’s possible with soluble synthetics, but will have slightly more than with organics.

Percentage W.I.N.

In order to determine the actual percentage of water insoluble nitrogen (W.I.N.), it’s necessary to do a little arithmetic. For example, if you have a 25-3-7 fertilizer with 7.6% W.I.N., multiply the 7.6 by 100 equaling 760. Divide the 760 by the total percentage nitrogen shown on the bag, In this case 760 divided by 25 equals 30.4 Thus 30.4% of the nitrogen is W.I.N.

Lawn experts have determined that fertilizers less than 15% W.I.N. are basically fast acting. Between 15 and 30% is medium and any more than 30% insoluble is a slow release fertilizer. A slow-release fertilizer is less lively to burn the lawn after application and is less subject lo being flushed from the soil by water.

Use a complete fertilizer

A complete fertilizer is one that contains all three of the primary nutrients: nitrogen, phosphate, and potash. Every state requires that the percentages of these three elements be prominently displayed on every bag of fertilizer. Always, the first number is nitrogen, the second phosphate, and the third potassium. An example is 24-4-8. These numbers state the percentages of nutrients in the bag compared to the total contents of the bag.

As a general guide, a 3 to 1 to 2 ratio of nutrients has proven to be good for home lawn fertilization. However. factors such as local climate, soil conditions, and the form of nitrogen in the fertilizer can influence what’s best in various localities. A 3 to 1 to 2 fertilizer could have a formula of 21-7-14. It is not critical for a fertilizer to be exactly this ratio, but something close to it is recommended. For instance, a higher nitrogen ratio of 6 to 1 to 2 (formula 24-4-8) is common.

Generally this ratio of nutrients is properly applied by using the products of a lawn food manufacturer in a label-directed way. There are general purpose types as well as those designed for specific grasses. These ratios are based on the demand of the growing lawn for these nutrients. Usually a lawn needs three to five times as much nitrogen as phosphorus and two times as much potassium as phosphorus. (Although nitrogen and potassium are needed by the plant in similar amounts, some nitrogen is flushed from the soil by water and is lost.)

Actual nitrogen

The amount of “actual” nitrogen is a term we have used throughout this site. It’s simply a convenient way to say how much fertilizer a lawn should receive, without ‘figuring the specific type or formula of lawn fertilizer you might use. For example, a 100 pound bag of 24-4-8 (24 percent nitrogen) contains 24 pounds of actual nitrogen. A 20 pound bag of 24-4-8 contains 4.8 pounds of actual nitrogen (20 pounds multiplied by .24 equals 4.8 pounds).

If you want to apply 1 pound of actual nitrogen over 1,000 square feet of lawn using this 24-4-8 fertilizer, you would use 4.17 pounds.

The directions on the bag will usually provide instructions as to the proper amount to use. Most labeled instructions follow the basic guideline of recommending application rates that supply approximately one pound of actual nitrogen per 1 ,000 square feet. There are exceptions; fertilizers with high percentages of W.I.N. or slow release forms of nitrogen are often applied at higher rates.

Fertilizer and pesticide combinations

In recent years, many combinations of pesticides and fertilizers have become available. Common types contain herbicides for broad leaf weed control or pre-emergence herbicides for crabgrass control. There are also products that include other pesticides for insect and disease control.

These products do have definite advantages. Considerable time, labor, and equipment are saved if two jobs can be accomplished in one. Less total material is handled and less storage space is required. In addition, the cost of the combined material may be less than the cost of the individual ingredients purchased separately. Most important, the pesticide can often be applied more evenly and closer to the recommended rate than if it was sprayed on the lawn.

The disadvantage of these kinds of products is the difficulty in making applications at the proper time, since the best time to fertilize is not always the best time to control insects or weeds. Be certain the growth cycles of the insects and weeds coincide with combination product applications for best results. A fertilizer combined with a pesticide is most useful if the advantages and limitations are understood.

When to fertilize

Few gardeners need to be reminded to feed their lawns in spring. It helps a lawn get a head start on pests, weeds, and the summer heat that’s soon to come.

By midsummer, heat and light intensity slow down the growth of the cool-season grasses. They usually remain green but are essentially dormant. We recommend, with only a few exceptions, no feeding of the cool- season grasses in mid-summer.

The most important time to fertilize cool-season grasses is in fall. Fall fertilization keeps the grass growing green and longer into cold weather, The lawn is stimulated to become more dense. Fall feeding also gives the lawn a chance to store food that will get it off to a fast start next spring.

Growth of the warm-season grasses peaks in midsummer then tapers off in fall, continuing at a slower pace until frost. The first sign of spring green comes when the soil is still cold. This is the time when lawn food with quick- acting forms of nitrogen pays off, making grass fully green sooner.

Warm-season grasses can also benefit from fall fertilization, with two exceptions. If winter weeds are a problem, their growth will be further stimulated by the feeding.

A heavy fertilization may also pro- mate a flush of succulent growth that, in some areas, leaves the grass more susceptible to cold injury. Otherwise, fall fertilization will keep the grass green and growing longer in the fall and promote earlier spring green-up,


In areas of the country with heavy rainfall, soils are typically acid, Grasses grow poorly in highly acid soils because of nutrient imbalance and toxicity. Acid soil is corrected by adding lime.

The only sure way to know if your lawn needs lime is through a soil test. However, liming is a way of life in many areas. In those areas, you already know your soil needs lime,

Soil acidity is measured by its pH. On a scale of 14, pH 7 is neutral, above 7 is alkaline, and below 7 is acid. If your soil pH is below 5.5, lime is necessary. A soil pH between 5.5 and 7.5 is good for most grasses and 6.8 to 7 is ideal. (Centipede grass is an important exception: it prefers more acid soil. Add lime if pH is below 4.5 enough to raise pH to 6.)

The easiest and best form of lime for lawns is ground limestone. Your soil test will provide recommended rates. Lime is best applied with a mechanical spreader.

How to apply fertilizer

There are five basic methods of applying fertilizers. Liquid fertilizers are applied by hand-held or hose-attached sprayers. Their basic faults are difficulty in applying the fertilizer evenly, frequent fills, and the amount of time it takes to apply adequate amounts. Read the directions on both the liquid fertilizer and the sprayer carefully. Rates are set up according to ratios of liquid fertilizer and water added to the sprayer. Also make sure all parts of the sprayer are attached and operational.

You can broadcast dry fertilizer by hand, but it requires a talented touch to be efficient. It often causes uneven streaking in the lawn. Use this method if only in very small areas or if there is no other alternative.

The use of a drop spreader is a very common method to apply a dry fertilizer. It requires more passes than a broadcast spreader, and is most useful on a medium-sized lawn. When using a drop spreader, overlap the wheels enough so no strips are left underfed, but also be careful not to double feed any sections. If this happens, you’ll have uneven greening in ; the lawn, or worse, fertilizer burn.

The use of a broadcast spreader is probably the easiest way of applying a dry fertilizer. There are two types – hand-held and push-wheel models. Each throws the fertilizer pellets over a wide area via a whirling wheel. Because they require fewer passes to completely cover the lawn, they are easier to use, especially on large lawns. Make sure you measure the throw width so you know how far to space your passes. This can be easily determined by running the spreader over dark-colored pavement for a short distance. (Note: some overlap is necessary for uniform coverage.)

Spreader settings:

Push-type drop and broadcast spreaders usually have adjustable settings which correspond to application rates on fertilizer bags. Although fairly accurate when the spreaders are new, they should be calibrated (the actual application rate tested) at least once a year. Hand-held broadcast spreaders can be calibrated the same way.

Drop-type fertilizer spreaders are also used to spread seed. Calibration is again necessary to make sure you apply appropriate quantities of seed.

The best technique for applying lawn food is to cover the ends of the lawn first, then go back and forth the long way. To avoid double applications, make sure to shut off the spreader as you approach the end strips. Keep the spreader closed while you are turning around, backing up, or stopped. For even and thorough coverage, walk at normal speed and keep the spreader level.

It you do happen to spill or drop extra dry fertilizer in one area, it should be scraped or vacuumed up. The area should then be flooded with water to avoid fertilizer burn.

After fertilizing, brush or wash out the spreader immediately alter use to avoid corrosion. Dry thoroughly before storing.

Lawn renovation

If your lawn deteriorates to the point that routine cultural practices such as mowing, fertilization, watering, and weed control, do not give the desired response, it is probably time to renovate. By renovating, it is possible lo renew your lawn without going to the trouble of completely rebuilding the lawn.

The University of Arkansas says: ‘Maybe you are wondering whether to destroy your old lawn and establish a new one or to renovate the old lawn.

Many factors can cause a poor lawn. Lack of adequate fertilizer is most common. Other problems such as mowing too low, lack of weed control, frequent light watering, shade, thatch, low soil pH, buried rocks or debris, drought-prone steep banks, wet soils, foot paths, diseases and insects – all contribute to a poor- quality lawn. Usually an analysis of the problems and solutions suggests that it would be easier to correct specific problems and apply a good cultural program to the existing lawn.”

Renovation may involve the use of heavy equipment available from a rental yard. There are many lawn service companies that specialize in these kinds of services. In any case, renovation is a chance to improve the overall quality of your lawn.


If you need to renovate your lawn be cause of thatch build-up, you have a lot of company. The spongy feel to lawns with heavy thatch is a result of a thick layer of slowly decomposing stems, roots, and debris. A thin layer of thatch, ‘A to ‘/a inch, may actually be beneficial because it buffers soil temperature and adds to the lawn’s resilience. This reduces the compaction of soil that results from heavy use.

If thick enough, thatch can actually be water repellent or “hydrophopic.’ A conscientious waterer may think he or she is watering enough, but actually the water never reaches the soil. Grass roots that grow in the thatch layer instead of the soil are naturally less drought resistant, since the moisture in the thatch evaporates much faster.

Insects and disease find thatch a particularly suitable place to inhabit. Since water cannot penetrate, neither can pest control materials.

Finally, variable thickness and density of thatch makes scalping by mowers almost inevitable. Dethatching of southern grasses is best done in spring just prior to spring green up,

Why thatch accumulates:
Thatch accumulates fastest in lawns composed of spreading type grasses. Notorious thatch builders include warm-season grasses such as bermuda and zoysia grass. In temperate climates the bent grasses and ‘Merion’ bluegrass are the worst, Dwarf-lype blue grasses also build up thatch.

What to do about thatch:
Soil penetrants, or wetting agents, only reduce the symptoms of thatch. They counteract its hydrophopic character, but the effect is short lived and definitely not a cure, Bacterial agents that supposedly breakdown thatch have also proven to be ineffective,

There are attachments for rotary mowers that may be helpful in thatch removal. A thatch hand rake that has knife like blades instead of the usual hard steel teeth can be used. As a last resort, a sod cutter can remove especially thick thatch if it has built up to impossible levels. (Note: this is only applicable for grasses that have underground runners.) Adjust the sod cutter to cut just above the soil level instead of below. Fixed, flail, and spring-tooth mowers are also available for dethatching.

The Mississippi State Extension says: “The most accepted way to dethatch a home lawn is by vertical mowing. The vertical mower is a specialized machine that thins the grass and brings much of the thatch to the surface of the lawn. You then sweep, rake. or vacuum this material from the lawn.

The University of Florida adds: ‘The blades of vertical mowers should be spaced differently for different grasses. Bermuda and zoysia grass can stand heavy thinning. Space blades only 1 inch apart. Centipede grass should be less severely thinned. Space blades 1 1/2 to 2 inches apart. Bahia and St. Augustine grass should be the least thinned. Space blades 3 inches apart.

“Zoysia and bermudagrass can be vertically mowed close to soil level in several directions without damage. Bahia, centipede, and St. Augustine- grass should not be vertically mowed closer than1 inch from the ground, They do not have the recuperative powers of zoysia and bermuda grass,’ Otherwise, the depth of penetration of the blade should be adjusted so that the blades will completely penetrate through the thatch layer and into the soil under the thatch.

These recommendations are valuable for realizing The recuperative powers of different grasses, but adjusting blades on a vertical mower is usually difficult. If you rent one it is probably impossible. Make only one pass on a slow-to-recover grass if you cannot properly adjust the blades.

Dethatch timing;
The best time to dethatch is just before the lawn’s most vigorous growth of the season. For warm-season grasses, dethatching should be done with the beginning of warm weather in late spring. Cool- season grasses grow best in spring and fall. The prime lime to dethatch is in the fall; the second best time is early spring.

About aeration
Roots need air as well as water and nutrients for growth. Lawns, especially those that receive heavy use, can develop compacted, air-deficient soil. Compacted soil also restricts water absorption. A foot-path worn into a lawn is compaction. To correct the many problems of compacted soil, lawn professionals have developed specialized tools and techniques.

Correcting compacted soil is described by a variety of names, including “hole punching,” “coring,” and ‘aerification.” All are based on the same principle: Hollow metal tubes 1/4 to 3/4 inch in diameter are pushed into the soil by foot or machine, to a depth of 3 to 4 inches, sometimes deeper. The soil should be moist when doing this, not too wet, not too dry.

Overseeding in winter
The only disadvantage of the warm season grasses is their winter dormancy. Scientists say that it is caused by a combination of low temperatures and winter sunlight. Whatever the cause, most lawn owners prefer all-year green color. Lawns can either be painted green or over seeded

Grasses for over seeding:
Annual rye grass is suitable for over seeding dormant bermuda grass. The seed is inexpensive and widely available. Use it heavily: about 1 0 pounds per 1,000 square feet,

Turf-type perennial rye grass is excellent for over seeding. The color is a dark green and the growth rate is slower than that of annual rye grass, resulting in less mowing.

The fine fescues are also good for over seeding. Use them alone or in combination with the rye grasses.

To be successful in over seeding, close mowing, dethatching, and (if possible) aerification are recommended. These steps help ensure close contact of seed and soil. As an alternative, mow close to the soil with a heavy, reel-type mower. Seed, and finish with a top dressing of peat moss or similar organic material. Don’t forget to water frequently until the new grass is firmly rooted into the soil.

The following spring, encourage the growth of the permanent lawn grass at the expense of the winter cover. Just before the late spring flush of growth, vertical mow again or mow close and fertilize. This will be enough of a shock to the winter cover and enough of a boost to the main lawn grass to reestablish.


Patching involves removing the weedy, dead, or damaged section of the lawn and replacing it with a piece of sod or by reseeding. It is always done with the same variety of grass as the present lawn. Many nurseries normally stock a small amount of sod just for this purpose.

Dig out the damaged area and loosen the soil underneath, If spilled gasoline or herbicide is the cause of the dead spot, remove several inches of the soil and replace It. Bring the underlying soil to proper grade and cut a piece of sod to fit.

Of course, patching can be done with seed, too. The process is the same as with any new seeding. Regardless of the method, remember to give close attention to watering for several weeks.

A renovating experience

We chose seed rather than sod to get the full growing experience. The lawn had many weeds, including unwanted bermuda grass and oxalis, requiring the most drastic kind of renovation. The entire lawn area was sprayed with a systemic herbicide, glyphosate. One week later we dethatched, aerified, and seeded.

Lawn weeds

Weeds are simply plants in the wrong place. The finest lawn grass plant is a weed in the vegetable garden and, likewise, dandelions are cultivated in some of the best vegetable gardens.

Most lawn weeds are easily eliminated. Mowing at the right height, fertilizing adequately, and good watering practices will go a long way in achieving a weed free lawn.

A healthy lawn will not be troubled much by weeds. Since problems and questions do come up, we’ve put together the following short course on weeds.

First, some definitions
Annual: A plant that lives only one year.
Perennial: A plant that lives for two or more years.
Herbicide: A chemical used to kill plants.
Pre-emergence; A term used to describe herbicides that are effective against germinating seeds before the plant emerges through the soil surface.
Post-emergence: A term used to describe herbicides that are effective after a plant breaks through the soil surface.
Contact herbicide; Kills plant parts covered by the spray. Affects only above-ground parts.
Systemic herbicide: Absorbed by the plant to circulate inside it, killing all parts, including the roots.

How weeds get in the lawn

Weed seeds are in most soils by the millions. They wait, dormant, until brought to the soil surface or until the lawn grass dies, when light and moisture start them growing. Some seeds can remain alive in the soil for many years. That is why some weed treatments are useful before you plant.

How to control lawn weeds

The more weeds you eliminate before planting will naturally leave fewer to battle later on. Following is one of the best methods of weed elimination. Simply keep the soil bare and moist for three or four months, and either till, or spray with a contact herbicide every three weeks, as the weed seeds germinate, If it’s awkward to leave your soil bare that long. try another method.

Fumigation is another pre-plant weed treatment. It too, usually involves time – at least three weeks. (Check the label directions.) Vapam makes a gas that kills many weed seeds and other soil organisms. It works very well, but is neither inexpensive or simple to apply, Also, it may harm nearby tree or shrub roots if roots extend into the treated area. Methyl bromide is another soil fumigant which works well and is fast (two to three days), but it is the most dangerous one to use, so much so, we don’t recommend ft for home lawns. unless used by a professional. A special permit is usually required, The only other pre-plant weed control method is the use of a pre-emergence herbicide. Some types will discriminate between the weed and the lawn grass seed; one is Tupersan.

Weed killers

Weeds are of two types; broadleaf or narrowleaf. Broadleaf weeds have more obvious, showy flowers. Their leaves have a network of small veins originating from a principal point or vein which divides the leaf in half. Dandelion and carolina geranium are typical broadleaf weeds.

Narrowleaf weeds are the grasses. They usually have hollow stems and long, narrow leaf blades with parallel veins. Dallisgrass and crabgrass are common narrowleaf weeds.

Another weed type, much less common, are the sedges. They look similar to grasses, but have triangular stems. It is important to stress the differences between these weed types. An herbicide that kills one type may not even affect the other. Also, it is particularly important to pay strict attention to labeled instructions. Many weed killers or pest controls are only effective within certain temperature ranges and stages of plant maturity. Be very careful when applying any chemical products. Don’t spray on windy days, and keep children away when you do spray.

Weed killers are either pre-emergent or post-emergent. The post-emergent types are further categorized as either contact or systemic. Chemical names are listed first. Trade names follow in parenthesis.


Benefin (Balan). Controls annual grasses in most lawns. Don’t use on bent grass. It will prevent ail seeds from germinating for up to eight weeks.
Bensulide (Betasan). Another control for annual grasses and certain broadleafs. Don’t try to reseed for four months after application.
DCPA (Dacthal), Especially effective on germinating grasses and seed of certain broadleaf species, including chickweed and purslane. Don’t use on new lawns and don’t reseed for 10 to 12 weeks after using.
Siduron (Tupersan). Effectively controls weedy grasses such as crab grass, foxlaif, and bamyard grass, It has the unique quality of not interfering with the germination of cool-season grasses such as Kentucky bluegrass.


Cacodylic acid (Contax, Phytar-560). Kills only upon contact, Very effective although repeat treatments are necessary before it will kill tough perennials such as bermuda grass. Kills all green-growing leaf tissue, does not move within plants to roots. Often used to clear lawns of existing growth, prior to renovation.
2,4-D Widely available in many forms and products. It is essentially a growth-influencing hormone that singles out the broadleaf weeds in the lawn, killing them, without damaging most lawn grasses.
MCPP (Mecoprop). Related and very similar to 2,4-D but safer to use on new lawns or sensitive grasses such as bent grass or St. Augustine grass.
Dicamba (Banvel). Particularly effective against clover, beggarweed, chickweed, knotweed, and red sorrel. It is a hormone-type weed killer as 2,4-D but is taken up through roots as well as through leaves. Be very careful using it around trees and shrubs or in areas where roots underlay the area to be treated.
Dalapon (Dowpon). Effective against all grasses. Usually used for spot treatment of undesired clumps of bermuda grass or tall fescue, Use in the West to eliminate bermuda grass from dichondra lawns. Use carefully, excessive rates can damage dichondra.
DSMA, MSMA, MAMA (available in many combinations under several trade names). Used to control grassy weeds such as crabgrass and foxtail. They kill mostly by foliage activity. Effective against hard-to-kill nutsedges.
Glyphosate (Roundup), Non-selective and systemic: It will kill both grasses and broadleaf weeds It is the best herbicide for control of bermuda grass, and is also useful against other perennial grassy weeds.

Insects and pests

There’s a patch of dead grass next to the driveway or a dead spot under the oak – was it caused by insects? The most difficult and important part of any lawn problem is diagnosing the cause.

Hundreds of kinds of insects and similar creatures live in a typical lawn. Some are so tiny they’re hardly visible; or others are quite large. Most do little damage to the lawn itself, and you’re not even aware of their presence. Other insects which are troublesome to people make their homes in lawns, but do not damage the grass. Fleas and ticks are in this category. But only a few serious lawn pests, such as sod webworm, the grubs of various beetles, and chinch bugs can destroy a lawn within a short time if conditions are right for their development.

The questions are: How to tell if the problem is caused by insects or a disease (or something else, such as gasoline or a dog). And if it is caused by insects, how can the damage be stopped.

Diagnosing the problem

In trying to discover the source of lawn damage, the easiest and most reliable method is to look, and look closely. Get down on your hands and knees and chances are, you will be able to see the pest in action. Some appear only at night, or only in a shady spot, or in a sunny corner. Specific habits and characteristics of the most common lawn pests are noted later.

Discovering insects in your lawn does not necessarily mean you have to spray. If there is a problem try to link in some definite way the symptom to the pest. For example, look for the green pellet-like droppings left by sod webworm. Remember too that damage is hardly visible until the pest population has built up to a considerable extent.

Many insects are only troublesome to certain kinds of grass. For instance, chlnch bugs are by far most damaging to St. Augustinegrass, wireworms rarely attack any grasses besides bahia or centipede. There are many examples like these. So to the extent possible, choose a grass that’s not bothered or at least doesn’t have a number one enemy.

Grow a healthy lawn. We don’t intend to make that sound simple or the solution to all problems, but a well-maintained lawn will be much less subject to serious insect damage. It is also able to recover quickly if problems do occur.

Finally, if your lawn is a perfect, frequently watered and fertilized putter’s delight, be prepared for some extra pest-related chores. In such a prime environment, more insect eggs are laid and more will survive.

Controlling lawn pests with chemicals

Insecticides are not the only answer to lawn pest problems. But, if and when you decide they are necessary, we feel you should know about them. There are many forms of insecticides available. If used properly, they are relatively harmless.

Here are some brief descriptions of insecticides commonly used by homeowners to control lawn pests. For the sake of simplification, we have listed the most frequently used trade or chemical name.

Aspon: This is a good control for chinch bugs and sod webworm. It works fast and is effective up lo two months. Water the lawn before spraying, then withhold water for two or three days to permit the chemical to do its job. Keep off the lawn until the chemical has been washed into the soil.
Baygon: Similar to Sevin (see below). Frequently used in baits. Controls chinch bugs, earwigs, and leafhoppers.
Carbaryl: Also known as Sevin. This chemical has been around a long time and is available in a wide variety of forms from many manufacturers. It has several uses for home lawn insect control.
Diazinon: Like carbaryl, widely available in many forms. One of the best for grub control. Protects against several lawn pests up to four to six weeks.
Chlorpyrllos: This is more commonly known by its trade name, Dursban. It provides effective control on chinch bugs, grubs, and sod webworm and many other insect pests as well. It remains effective for four to six weeks.
Metaldehyde: Look for this ingredient in slug and snail baits. Use it where snails hide, such as around ground covers. Both snails and slugs hide in cool, moist areas during the day and come out at night. They love new lawns and dichondra.
Methoxyclor: A common ingredient in many spray mixes. Generally, it is very useful and has about a two month residual.
Mesurol:This is a very effective killer of slugs and snails. Lightly water the area before spreading the bait.
Milky disease: (Biological control) This is a disease natural to Japanese beetle grubs. It has no effect on other kinds of grubs or any other insects. It is established in soils over a period of years where Japanese beetles are present. It is slow to establish and control is not one hundred percent, but it will keep the beetles in check.
Bacillus thuringensis: (Biological control) Similar to milky spare disease in that it is very specific. It will kill only caterpillars (butterfly and math larvae). Very useful in many situations, although it is not widely used on lawns.

Of course, the best information on these and other pest control products is on the product label. We must stress, read the label in the nursery or garden shop before purchase and again, carefully, before use.

Lawn diseases and similar problems

As we mentioned in the section. ‘Insects and pests,” diagnosing lawn problems can often be difficult, especially if considerable time has elapsed between the cause of the damage and the diagnosis. Many times the problem will be attributed to an insect or disease, when actually the climate, environmental conditions, or cultural practices are the cause. Mowing height, competition from tree roots, chlorosis, soil compaction, improper watering, and herbicide damage are some of the many factors that either cause the symptoms or are related to the development of the disease.

The importance of proper lawn care

It is repeated again and again in this site that proper maintenance will reduce lawn problems. This is especially true when it comes to lawn disease. Most of the diseases that attack typical home lawns are due to improper management. Thatch is one of the most important factors that govern the frequency of disease in the home lawn. Thatch restricts the movement of air, water, and fertilizers into the soil, and generally weakens the lawn. This type of lawn is naturally much more disease prone.

When and how much you fertilize a!so has an important impact on disease development. An over-fertilized lawn, as well as an under-fertilized lawn, are more disease susceptible. Timing is also critical. For example, if you give a cool-season lawn heavy doses of growth-stimulating fertilizer in late spring and summer (periods of naturally slow growth), it becomes increasingly susceptible to leaf spot and Fusarium blight. It’s important to follow a fertilizer program that conforms to the growth cycle of your particular lawn grass. The lawn experts say it best: “Let the grass grow, don’t make it grow.”

Watering practices also relate to disease frequency. Lawns that are watered deeply but infrequently usu- ally have fewer disease problems. Constantly wet grass in poorly drained soil promotes disease.

Lawn diseases are easier to prevent than to cure. Follow these steps to prevent diseases from becoming established in your lawn.
– Plant a grass type and variety that is adapted to your climate.
– Mow at the proper height.
– Fertilize at recommended rates and on a schedule that fits the growth cycle of your cool or warm-season grass.
– Water deeply and infrequently and only when the lawn needs it.

When a serious disease does attack your lawn despite adherence to these preventive measures, use of a chemical control is necessary.


There are over a dozen chemicals commonly sprayed on lawns by homeowners to prevent and control disease. They are categorized as either “systemic” or “non-systemic,”

Systemic fungicides work from inside the plant, so are usually the most effective. They are, however, very specific and will control only certain diseases.

Non-systemic fungicides work from outside the plant. They are best used before a disease starts. For example, if you know from past experience a certain disease will attack your lawn in two weeks or so, start spraying the appropriate fungicide now. This way the disease can be prevented.

Look at the chart for a breakdown on the uses of the various fungicides. Use the succeeding information to help identify and control any diseases that occur in your lawn. For the sake of simplification, chemical names rather than trade names are used to describe controls in the disease descriptions.

Common Name/Trade Name



Dollar spot and melting out, rust, snow mold. Non-systemic

Tersan 1991
Cleary 3336

patch, dollar spot, j
Fusarium patch, Fusarium
blight, powdery mildew, and
stripe smut. Has systemic action


Melting out, damping off, and
Orthocide stripe smut. Non-systemic,
contact only

chloroneb/Tersan SP

blight, grey snow mold.

chlorothalonil/Daconil 2787

Brown patch, dollar spot, Fusarium patch, melting out, and red thread. Non-systemic fungicide


Brown patch, dollar spot, leaf spot. melting out. powdery mildew, snow mold. Non-systemic


Damping off, pythium (grease spot). Non-systemic




Melting out. Non-systemic, contact only

mancozeb/Dithane M-45

Red thread, rust, and melting out. Non-systemic

maneb/Dithane M-22

Rust. Non-systemic


Rust. Non-systemic


Brown patch. Melting out. Slight systemic activity

thiabendazole/Mertect 140F

Brown patch, dollar spot, Fusarium patch, snow mold. Non-systemic

Thiophanate methyl/Topsin Spot Clean Fungo-50

Brown patch, dollar spot, Fusarium blight, Fusarium patch, stripe smut. Systemic


Growing lawns in the shade

The establishment and care of a good quality lawn in the shade is a real headache for many people. It need not be. Many beautiful lawns are grown in the shade of spreading trees. One of the measures of success is understanding the relationship between the tree and the grass underneath.

First of all, you must realize that there are many types of shade – light, half, dappled, full, and heavy. Few grasses will grow in full or heavy shade. Although it’s difficult to figure out exactly, a lawn needs about 50 percent of the sunlight passing through a tree to sustain it underneath.

Beating the competition

The grass growing underneath your trees is competing with the trees for water and nutrients, but most importantly, light. If left alone, and the shade is heavy enough, the tree will almost always win. The grass will become thin and spotty or gradually die out altogether.

Your job is to supply the requirements of the grass without harming the tree. Of course, if the tree is not a functional part of the landscape, you may decide to remove it in favor of the grass.

One of the first steps towards a successful lawn in the shade is to plant a shade-tolerant grass. Certain varieties are more shade tolerant than others.

In areas of established turf, you may want to do small scale renovation and reseed with a better adapted grass. We also know of people who reseed every year with turf-type rye grass to keep fresh new grass under trees.

The choice of grass may require some forethought. If you have recently planted a young tree, shade probably isn’t a problem now, but may be in the future.

If you are considering planting trees in your lawn, plan ahead. Choose trees which cast filtered shade, and don’t over plant. Several lawn trees are listed in the section, “Lawn tips.”

If a suitable grass is already growing under your trees, good maintenance practices will, of course, help the shaded lawn. However, there are some slight modifications of normal practices that will help even more.

Mow the lawn higher, at the highest cut suggested.. More blade length means more light trapping ability. If fertilization is desired, consider soil injections for the tree instead of applying fertilizer directly on the lawn. A major problem of grass in the shade is over fertilization.

Watering deeply (but not over watering) is especially important when trees are growing in the lawn, Shallow watering causes surface rooting which in turn causes mowing problems and allows the tree roots to rob the lawn of its nutrient needs.

If surface roots are already a problem. most trees can stand some root pruning without doing them much harm.

Don’t leave the leaves

Grasses growing in shade arc more tender than those growing in full sun, so pay close attention lo insect and disease problems.

Fallen leaves and heavy grass clippings can smother growing grass and increase damage from pests. This is particularly true in shaded areas.

Too much shade

The most obvious, and sometimes the simplest solution to shade, is to prune the tree. Through proper thinning, as much as 40 percent of a tree’s leaf surface can be removed without drastically changing the appearance of the tree. In fact, it usually enhances it.

Sometimes there are too many trees. Removal of a few can be helpful not only (or the lawn. but for the trees that remain. You might also want to check into other alternatives such as an attractive stone or bark mulch.

Lawns in your area

This information is really about climate, and the effects of climate on lawn growing. The length of growing season determines how much fertilizer your lawn will need each year. Summer rainfall patterns tell which lawns need irrigation systems or at least regular watering.

Obviously, winter low and summer high temperatures delineate to a great extent which grasses can be grown where.

In our earliest research, we questioned lawn owners around the country, who revealed a strong desire for specific information concerning the lawns in their climates. We heard comments like this one from Florida; “Most lawn books are limited by various geographical problems. I would like a book on growing lawns where I live”’ An individual from Texas said, “None of the books about lawns have much use around here”.

The South is big and the grass climate in Tennessee is very different from the Florida climate. Compare the climate of Tampa, Florida, to that of Jackson. Tennessee, for instance. The Tampa climate is almost tropical. Winter temperatures never drop anywhere near freezing and they receive an average of 60 inches of rain per year. Warm-season grasses are the rule and since the growing season is year-round, the fertilizer program goes through the whole year also.

Jackson, on the other hand, has January low temperatures that average 15 degrees F. This is much too low for most warm-season grasses. Although many of the zoysia and hybrid bermuda- grasses make their way into Tennessee, most of the beautiful lawns in Jackson are made up of cool- season grasses – Kentucky bluegrass or fescues. This is the case with many northern or high elevation areas of the South.

Local characteristics such as soil types and summer highs or winter lows, play an important role in which type of grass you grow and how you care for it. Knowing this kind of specific information will help you grow a better !awn.

About climate
Climate professionals use phrases such as “percent of sunshine” or “July days above 90″” the same as listed below. Here is what such words mean and how they relate to lawn growing.

Total inches rain. The average annual rainfall including snow, hail, and sleet. Rainfall, within a wide range of temperatures, is the most important environmental factor promoting or restricting growth of all plants. In some areas, excessive water is a problem. Caused by either too much rain or too slow drainage, wet soil will retard growth as surely as drought.

Rainfall can be plentiful in certain parts of the South but falls all at once or within a short season, thus is scant at other times of the year.

Too little rain is a more familiar problem. Soils that lose water rapidly by drainage (sandy soils) are more drought prone while lawns in heavy soils (clay) are less susceptible to short periods without rain,

Inches July/August. Referring to rainfall, this figure tells how much waterfalls naturally when the lawn needs it most, during the hot months of the year. A lawn’s water requirements during summer is determined not only by grass type and soil, but also by the temperature and humidity.

July % of sunshine. Each day there is a certain amount of sunshine possible. This amount varies from the least on December 22 to the most on June 21, The actual number of sun- shine hours also varies by latitude. In south Florida, December 22 has about 10 1/22 hours and June 21 just less than 14. Percent of sunshine is figured by comparing the amount possible with the amount actually received, This figure indicates the number of cloudy, overcast days that occur in July.

July day above 90°F. The number of days in July when the temperature goes over 90″F. is one of the best guides to the grass type you should grow. It also indicates the stress a cool-season grass will be subjected to. The best temperatures for growth of the cool-season grasses such as Kentucky bluegrass are between 60 and 75°F. Warm-season grasses grow best when temperatures reach into the 80’sand 90’s.

Average maximum/minimum temperatures. These are the monthly averages of the daily temperature extremes. As such they are the best available guide to questions such as when to plant, water, and fertilize.

Lawn calendar

Temperatures control the timetable but not the calendar. However, we must use the calendar to express time. The South is a diverse area, For example, temperatures in the South for the month of March range from 53°F. in Lexington, Kentucky to 80°F in Miami, Florida.

The many lawn climates of the South The South is big. We’re talking about
1. South Atlantic Coast influence,
2. Gulf Coast.
3. Arid regions of the South.
4. Cooler northern regions.

We’re talking about growing days (days between frosts) varying from 187 to 365.
The important regions in the southeast are:
1. Coastal Plain
2. Piedmont.
3. Mountains


Winter weeds: In areas of the South where weather warms up early, pre-emergent treatments for crabgrass, spurweed, and annual bluegrass are applied about one month before seeds germinate (see crabgrass control under March listing). You can also spot-treat wild garlic as it emerges with 2,4-D, or other recommended chemicals.
Fertilizer: In the warmest areas of the South where a lawn may stay green all year, bermuda, bahia, St. Augustine and zoysia grass can benefit from the boost they’ll get from an early feeding.
Insects: If it’s warm enough to apply fertilizer where you live, then grubs that overwintered in the soil should be near the surface, where they can be controlled. Get rid of them now if you missed the chance last fall.


Watch for the first signs of green growth as bermuda, St. Augustine, centipede, carpet or bahia grass begin to grow faster. It can come as early as January or February in the mildest sections and it may not come until April in the upper South. When spring does arrive, temperatures about 70°F. signal the opening of the lawn season.

Mowing low: Set your mower to cut just above the new grass blades to warm the soil and expose new growth to more light. If you had a temporary winter lawn of rye grass or fescue, low mowing will discourage its growth and give your permanent lawn a chance to take over.

Fertilizer: Figure that 1,000 square feet of lawn needs the following amounts of nitrogen per year: 4 to 6 pounds for St. Augustine grass, 6 to 12 pounds for the improved bermuda grasses, 4 to 6 pounds for bahia, 3 pounds for carpet and centipede grass, and 4 to 6 pounds for zoysia grass. For more information, see the section on fertilizing. Not all warm-season grasses require fertilizer at this time.

Patching: Repair winter damage with pieces of sod, sprigs, or plugs. You may want to use seed if you have Kentucky bluegrass, other cool-season grasses, or bahiagrass.

Sodding: A practice that can actually be done at any time during the growing season, it is normally done during spring and fall.

Crabgrass: You can do your lawn a favor if crabgrass or annual bluegrass was a problem last summer. Seeds left over from last year sprout when temperatures reach 65° to 70°F continually for four to five days, To stop their germination, use a pre- emergent barrier a month before seeds begin to germinate. This should be about February in the mildest areas, in mid-March in the Coastal Plain, and the end of March in the upper South. Pre-emergent chemicals like Tupersan should be used if you plan on doing any spring seeding. They kill crabgrass but not most lawn seeds. Read the label to be sure.

Disease: The cool, moist weather of spring favors development of several fungus diseases. Cottony blight on ryegrass and leaf spot are among those present now and again in the fall. Dollar spot can occur anytime until late summer, especially with high humidity and temperatures of 80°F.


Warming weather makes May and June prime months for planting a warm-season grass lawn. You can plant as late as July, but later plantings may not have time to establish before cooler weather. Common bermudagrass lawns can be started from seed, but improved bermuda, St. Augustine, and most of the other warm-season grasses are started vegetatively. Be sure to control weeds so that the lawn can establish quickly without competition for light, water, and nutrients.

Dethatching: Scrutinize established lawns for buildup of thatch — particularly in bermuda and St.Augustine grass. Thatch blocks out air and water. and fosters pests and diseases. Thin it
out with a heavy rake if the area is small, rent a power rake (renovator), or hire a lawn service company for larger lawns.

Fertilizer: This month feed warm-season grasses except carpet and centipede. If a lawn stays yellow in spite of feedings, the problem may be a shortage of iron called chlorosis. The condition, common to centipede and other Southern grasses, can be corrected with sprays containing iron. This is another time for a light application of fertilizer on bluegrass, fescue or ryegrass. They will make good growth before the hot weather of summer slows them down.

Broadleaf weeds: Blooming dandelions are a sure sign of weeds, but plantain, sheep sorrel, and many others that are less obvious are just as troublesome. Most weeds grow well at 70°F and are most vulnerable to herbicides while still young. In addition, weed killers formulated for their control are most effective in warm but not hot weather. If tough-to-kill weeds like oxalis and spurge are pestering your lawn.


A lawn that has received the right care should look like a masterpiece this month, though cool-season lawns begin to slump with the onset of hot weather (proper watering will help keep them looking their best).

Fertilizer: Bermuda and zoysiagrass need fertilizer this month. Bluegrass, fescue, and ryegrass remain slow growing until fall brings cooling weather.

Insects: Chinch bugs are a part of life to St. Augustinegrass. The bugs thrive in the lawn’s sunniest, driest spots. Infested patches turn yellow, then brown. Follow this test to make sure that the problem is caused by chinch bugs. Start near the edge of the damaged area and push a bottomless can down into the lawn; keep it filled with water for about five minutes. If chinch bugs are there, they will float to the surface. Treat the whole lawn as chinch bugs spread quickly. Another likely June pest is the sod webworm. You’ll probably notice adult moths first — fluttering close to the lawn at dusk, laying eggs. Two weeks later, the worms hatch and start feeding on grass blades at night. To confirm their presence, examine dead patches for larvae. Look for them during the day; they curl up in the thatch of the turf.

Armyworms also feed on lawns, but they’re twice as big as webworms, and feed in broad daylight. Control is the same as for sod webworms. It is best to apply these insecticides in the late afternoon or evening.

Grassy weeds: If you have crabgrass in your lawn, it’s big enough to be noticeable by now. You can stop adolescent and mature growth with post- emergent annual grass controls. Other grassy weeds become prominent this month. Dailisgrass and nut- grass are hard to get rid of and may require monthly applications for control. In June, you may also notice Poa annua, (annual bluegrass). It’s light green and pretty enough in spring, but when hot weather comes it sets seed and dies in unsightly patches. There is not much you can do about it now, wait until August and September.


Hot weather calls for some changes in a lawn maintenance routine. Keep watching for sod webworm and chinch bugs. Continue feeding as needed for your type of lawn. Bermuda and zoysiagrass favor feeding in both July and August. Bahia, carpet, St. Augustine, and centipedegrass can skip the August application. Do not overfeed. Excessive feeding favors sod webworm and army worms.

Mowing; Raise mowing height to provide more shade for roots. This is important if you want to keep a cool- season grass from going dormant.

Watering: Watering is the most important job for these months. How much you water depends on your kind of soil and climate, but the general rules of watering deeply and infrequently hold true under most conditions.

Disease: The most likely summer lawn disease is brown patch. Warm humid weather favors its development. To keep it from spreading, especially if favorable weather continues, mow, rake, feed, and water thoroughly. An adequate safeguard against brown patch is simply good maintenance.


Even as weather cools, summer routines should be kept in mind — feeding, chinch bug control, disease prevention, watching for sod webworm.

Fertilizing: It is particularly important to continue regular feeding — the last feeding of the year (except in the Deep South) is an important one (or St. Augustine, and centipede grass. Bermudagrass can also take another dose. For Kentucky bluegrass, fescue, and ryegrass, the months ahead are the most important feeding times of the year — they are building up root systems and storing reserves while producing less top growth than they did in the spring.

Planting: It’s the best time of the year to start a cool-season lawn. Warm temperatures will germinate seeds, and, with the coming of cool weather and fall rains, you’ll have to do less watering and the lawn will establish quickly.

Grassy weeds: Now is the chance to begin a campaign against Poa annua. The idea is to prevent seeds from sprouting this fall. Early this month, apply a pre-emergent herbicide labeled for this purpose. Apply it again next spring.


Fertilizing: In early fall, feed bermuda, zoysia, bahia, and St. Augustine one last time to build strength for winter, and help get it off to a fast start in spring. This is the most important feeding of the year for a cool-season lawn. Your lawn will have more strength in winter, a more vigorous root system and start stronger early next spring.

Overseeding: If your bermudagrass lawn goes dormant in the upper South, you may want to overseed with ryegrass or fescue. An alternative is to color the lawn. Rake the lawn and mow closely before seeding. Sow seeds and keep moist until germination.

Broadleaf weeds: The return of cool weather gives you another crack at broadleaf weeds. A good many kinds start out in fall and are at their most vulnerable stage. Remember, broadleaf herbicides work best in warm (not hot) weather.

Good timing
Timing of course is an important part of lawn care. But it’s Just one of the important steps to a good lawn. You must put all the steps together. 1. Use adapted grasses. 2. Mow regularly at the correct height. 3. Fertilize according to what’s best for the adapted grass. 4. Kill broadleaf weeds at the best time. 5. Prevent crabgrass if necessary. 6, Keep insects under control. 7, Remove thatch when necessary. 8. Protect against diseases that kill the lawn. 9. Irrigate to keep the lawn in good condition.

Lawn tips

A website about lawns is never complete. Here are some miscellaneous tips we’ve pulled out of previous chapters to serve as handy information in a concentrated form.

Trees in the lawn

The main cause of damage to trees in the lawn results from lawn mowers bumping the trunk. Any wound in the bark is an invitation to insects and disease. Three wooden stakes placed about one foot from the trunk can be used to protect young trees. Grass growing against the trunk of a young tree can severely retard the tree’s growth, even if additional water and fertilizer are applied. A 30-inch in diameter ring of mulch around the tree can give it a good start. Keep mulch away from the trunk.

Grade changes can kill many trees, Piling soil around the trunk can suffocate surface roots. Removing soil either damages roots or exposes them to drying. During the establishment of a lawn, any grade changes around trees should be gradual. Changes of more than a couple of inches require the use of retaining walls or dry wells, which are best extended to the drip line of the tree.

Some trees that are especially adapted to growing in southern lawns include:
Carya illinoinensss
Cercis canadensts
Chionanthus spp.
Crafaegus spp.
Koelreuteria spp.
Magnolia spp.
Pyrus spp.
Pinus spp.
Ouercus spp.
Fringe tree

Instead of a lawn, ground covers can be grown under trees, If the shade is more than 50 percent, ground covers are a better solution than turf.

Changing grade

Even after a lawn is established, you may want to change the grade to correct water run-off or level high and low areas. Grass will grow with the addition of small amounts of sand, organic matter, and top soil. You will find change of grade is simpler if you go at it gradually, adding or subtracting a little fill at a time.

Leaves on the lawn

There are leaves that easily blow away and there are leaves that are big and determined to stay on your lawn. Some trees drop their leaves in a short time while others seem to drop forever. Regardless of when and how they fall, rake them up and add them to the compost pile. They will decay faster if they’re shredded. Leaves do not act like a blanket lo keep the grass warm. They actually smother the lawn, especially when it’s wet, thus depriving the grass of light,

Lawn clippings as a mulch

If you use lawn clippings as a compost or mulch in the vegetable garden, take care that the lawn clippings are free of 2.4-D, and other broadleaf weed killers. 2,4-D affects plants in various ways. Continuous mulching of tomatoes with treated clippings has resulted in distorted plants. Let clippings treated with 2,4-D settle into the lawn, or discard,

Washboard effect

Turf grass areas regularly cut with a power mower may develop wave-like ridges running at right angles 1o the direction o1 mowing. Alternating directions of cut will help correct these ridges.

Mow less often

Recently tested growth regulators have displayed the ability to slow lawn grass growth for 5 to 8 weeks. Lawns are mowed only half as often when the chemicals are used.

Several difficulties prevent marketing for home use at this lime:
1. The regulators work best only on single-grass lawns.
2. Slowed growth may favor weeds and disease.
3. Weather, stage of growth, fertility status, and time of application all effect results.
4. Improper application can cause damage to the lawn.

Presently available growth regulators are best adapted for difficult or impossible mowing situations; along fences, wails, or on steep, unmowable slopes, for example,

Paving block lawns

Concrete paving blocks combined with turf grass will produce a new kind of multi-use lawn area. A paving block lawn can be used as a driveway, parking area, or pathway. They are similar in appearance to over sized checker- boards, with alternating squares of supportive blocks and planting holes. An average-sized block covers about three square feet. Standard concrete building blocks can also be used.

Planting a lawn with paving blocks is a simple operation. If the proposed area will be required to support heavy weight, such as a driveway, a solid base for the blocks should be prepared. The paving blocks are placed in position side by side, and the holes filled with a quality soil Seed or sod plugs can then be planted, the same as for any new lawn. After establishment, the weight of vehicles or heavy foot traffic is supported by the blocks, not the turf.

There are many advantages to this type of lawn. They are naturally more attractive than bare soil or artificial surface, and are cooler and produce less glare. During the rainy season water runoff is less due to the lawn’s greater absorption qualities.

Different grass types produce different effects. A vertically growing grass such as tall fescue will obscure the blocks completely. A horizontal grass such as bermuda will stay low, allowing some of the paving block to remain exposed, providing a textured pattern.

The cost of a paving block lawn will of course vary with the situation. As a general rule, however, it should be the same or even less than poured concrete.

New sod lawns

Prevent tearing corners of sod that has not yet rooted by mowing at a 45 degree angle to the edge. Such a mowing pattern has less tendency to lift sod.

Lawn colorants

Many of the objections that were expressed when colorants were first introduced are no longer valid. Quality colorants will not rub off, walk off or wash off. They have become fade-proof, non-toxic and long wearing. The first application of colorant should be made immediately following the first killing frost. To prepare the turf, mow the grass to one inch or less. Then mow at right angles to the first pass to provide as even a turf as possible. All clippings, litter and debris should be removed before the colorant is applied. Mix colorant according to directions on the label. That ratio will vary, depending on the color intensity desired. One gallon of colorant will normally cover 4,000 square feet of turf. The turf should be colorized twice, the second application made at right angles to the first to assure uniform color.

Treat the cause, not the symptom

If a trouble spot develops. search, then treat the cause, not the symptom, Here are some examples: A dry spot that appears repeatedly in the lawn may result from a lack of organic matter, or improper grading.

Not enough depth to the soil above bedrock, or buried concrete or debris will also cause drying.

Moss: If you have a problem with moss, there are temporary cures, but for a permanent solution, look for the cause. Moss is usually the result of improper drainage and shade, not soil acidity. Other factors contributing to moss are poor air circulation and insufficient light, which slow the evaporation of water from the soil.

Powdered copper sulfate at three tablespoons per 1,000 square feel or ammonium sulfate at 10 pounds per 1,000 square feet are chemical controls which may be used, Also, fertilizers containing ferrous and ferric ammonium sulfate wilt control moss, Be aware, however, this amount of ammonia sulfate may furnish too much nitrogen for cool-season grasses if applied in late spring,

Mushrooms: After prolonged periods of wet weather, you may notice mushrooms coming up in the lawn. This often indicates the presence o1 construction debris or old tree roots and slumps that are decaying below the surface. It may be years after construction before the mushrooms appear. There is no effective chemical control for these fungi and they cause no damage to the turf. However, if you feel they are unsightly and poisonous, remove them with the lawn mower or a bamboo rake.

Moles: A single mole can range over several acres, digging several thousand feet of tunnels. The structure of the surface tunnels and the temporary way in which they are used makes mole control difficult. Gases introduced into these tunnels are ineffective because they will quickly diffuse through the thin overhead sod covering. Since moles are primarily carnivorous, it is difficult to poison them. The most practical control is to trap the animal, which can be very time consuming, or to remove their food supply so that they migrate else where. Until their primary food source, grubs and earthworms, is eliminated, moles will continue to move in to feed. If you have moles, the best solution is to treat for grubs.


The southern grasses respond differently to dethatching by vertical mowing. We quote the Texas Agricultural Extension Service bulletin MP-1180;

“Bermudagrass and bluegrass respond favorably to vertical mowing, but care should be taken with non- rhizomatous turf grasses such as St, Augustine grass, If the St. Augustine grass is not well-rooted, serious thinning can occur as a result of vertical mowing. Equipment blades should be spaced 1 1/2 to 2 inches apart and should not penetrate loo deeply into St. Augustine grass turf. Vertical mowing can best be accomplished in early spring, just prior to the initiation of new growth. Fall vertical mowing of bermuda grass may cause an increase in clover, annual bluegrass, and other winter weeds. Likewise, early summer dethatching of Kentucky bluegrass may increase the infestation of crabgrass.

Centipedegrass decline

Centipede grass is hardy in areas of the south from as far west as Galveston, Texas, to Baton Rouge, Louisianna and Charleston, South Carolina. We quote from the University of Georgia leaflet No. 177; ‘Centipede grass is adapted to south Georgia and survives as far north as Athens or Atlanta during most years, Centipede is one of the prevalent lawn grasses of middle and south Georgia. Its popularity is due to ease of establishment and low maintenance requirements. The grass can be planted from sprigs or seed. The fertility and soil pH requirements are considerably lower than most grasses, and it requires less mowing as well. Its tolerance to most turf diseases and response to water during drought conditions are other desirable traits. Sometimes centipede grasses low maintenance requirements give the homeowner a false sense of security in that the turf is often neglected which results in inadequate maintenance. In some cases, it is managed like high maintenance grasses. Either attitude leads to mismanagement problems which results in the decline of the turf. Each spring many Georgia homeowners encounter a problem with centipede grass called centipede decline. Normally, lawns of this grass grow quite well until the third to sixth year after planting. After this time, areas in some lawns may fail to grow or ‘green-up’ in the spring or summer.’ To prevent decline take the middle course. Neither under or over-fertilize. Don’t allow thatch to build up. Mow no higher than 1 to 1 1/2 inches.

Lawns in Florida

Tampa Lawn growing is different compared to many other areas of the South, hence our special focus here.

Many different grasses are available to Florida lawn growers: bahiagrass, bermudagrass, carpetgrass, centipedegrass, St. Augustinegrass, and zoysiagrass. Of these only bahia, common bermuda, carpet, centipede, and Zoysia japonsca can be started from seed. (The remaining grass types must be started vegetatively.) The best time to seed is during the spring and summer months — April through September. This is the time of year when conditions are most favorable for germination and growth of warm- season grasses. In northern Florida, young grass seedlings may winter- kill if planted too late in the fall. Spring and summer seeding also lakes advantage of Florida’s rainy season, so the need for irrigation is reduced.

St. Augustinegrass is by far the most popular and commonly planted grass in Florida. It grows throughout the state and is especially well adapted to coastal areas.

Advantages of St. Augustinegrass.

St, Augustinegrass will grow in many types of soil, from pure sand or muck to the shell and marl soil of southern Florida. It will persist on both wet and dry sites, and has good salt and shade tolerance, When properly maintained, St, Augustinegrass produces an attractive, dark green lawn that is very tough, withstanding considerable wear.

Some disadvantages

St. Augustine grass is not perfect, of course. Its biggest problem is susceptibility to chinch bugs. They can be especially active when the weather is dry and hot.

St. Augustinegrass must be established by sod, sprigs, or plugs, rather than by seed. These establishment methods entail somewhat greater cost and effort. Thatch may be another problem since St. Augustine is a fast-growing grass in Florida. For this reason, it requires medium to high levels of maintenance, including frequent mowing, medium-to-high fertilization, and periodic control of pests.

Varieties. There are six varieties of St. Augustinegrass that are generally available. The best are:

‘Roselawn’ is primarily a pasture grass. It will make a very coarse, open sod and is not recommended for home lawn use. !t is very similar to common St. Augustinegrass.

‘Bitter Blue’ is an improved selection which makes an excellent home lawn. It has an even, dark green color and leaves are shorter and closer set, which produces a particularly dense lawn if well maintained.

‘Floratine’ is similar to ‘Bitter Blue’ but is finer textured and produces a lower growing, more dense sod. If available, use certified ‘Floratine.’ A blue certification lag should accompany the sod, guaranteeing its purity.

‘Scotts 1081’ is vigorous and fine textured and will make an attractive lawn if properly cared for.

‘Floratam’ is available from certified sod growers and also produces a high-quality lawn. Prime advantages over the others is resistance to chinch bugs and SAD virus. ‘Floratam,’ however, is not as fine textured or low growing as ‘Floratine,’

Fertilizing. For northern Florida lawns, apply a complete fertilizer such as a 24-4-8, 21-4-4,or similar formula in both spring and fall for minimum maintenance.

An optimum program for northern Florida requires fertilizer applications March, May, July, and September. More fertilizer is needed in the southern part of the state, primarily because of the longer growing season.

Many factors usually combine to cause a poor lawn. Lack of fertilizer is by far most common. Other problems, such as lack of weed control, mowing too low, to much shade, or drought. Usually it is easier to correct specific problems and apply a good cultural program 1o the existing lawn.

An optimum fertilization program for St. Augustinegrass in southern Florida includes fertilizer applications every other month. Follow label directions as to amounts and temperature restrictions.

Pests and disease. Chinch bugs are the most damaging insect pest. Sod webworms, armyworms, and mole crickets may also damage St. Augustinegrass.

Brown patch and grey leaf spot are the two most serious diseases. Occasionally, dollar spot, helminthosporium leaf spot, and rust are problems. Nematodes may be a problem if growth is poor and other treatments such as fertilizing, bring no response.

Cautions Read the label every time you spray or dust and pay attention to cautions and warnings. Mix sprays on a solid level surface to lessen spillage. Avoid spilling pesticides on the skin or clothing and wash exposed areas thoroughly with soap and water. Do not eat or smoke while spraying. Keep all chemicals out of reach of children. Store them in a locked cabinet or high on a shelf. Set aside a special set of mixing tools, measuring spoons, and graduated measuring cups. Use them for measuring and mixing sprays only. Be sure to keep all chemicals in their original, labeled containers. Store lawn fertilizers combined with weed killers, separately from garden fertilizers to prevent accidental misuse.

Let’s say it again
There are many descriptive terms in this website. Many hold such importance, they should be explained and described again and again. Aeration and compaction are two such terms that every lawn keeper should engrave on stone. Compaction can be caused by children playing on a wet lawn. Heavy machinery driven across a lawn forces air out and can compact soil. Paths across a lawn will also compact the soil, drive air out, and will often kill the grass. You can get air into the soil, (aerification), by the use of an aerator which extracts plugs of soil from the lawn, allowing air to reach the root zone. The best time to aerify is when the lawn is actively growing.