Most lawn owners need help with forces beyond their knowledge. Unfortunately, many lawn experts talk over the heads of “Mr. and Mrs. Suburbia,” who have not been trained in soils, plants, fertilizers, machinery, and chemicals.
It is not feasible to develop a timetable for lawn management because Nature and water companies are what they are; one can never be quite sure of being able to stick to a pre-arranged program.
“Across-the-hedge” advice always will be with us with varying degrees of misinformation, but understanding why and how we do certain things to lawns will ensure a greater chance for success.
Understanding Facts About Good Soil
A few facts about soils should be understood. First, any resemblance between good soil and the stuff usually left by the contractor is strictly accidental and unintentional.
Only a few contractors save the good topsoil from redistributing on the lawn after the house is completed. Therefore, most gardeners are forced to grow a lawn on the soil they have as money or good soil (or both) is usually unavailable.
Poor soils can be improved by periodic cultivation, aerifying, or loosening. Heavy liming and fertilization.
Virtually all soils, sandy soils included, may become compact and crusted on top. Compaction and crusting are natural results of water and traffic. Crusted, hard soil prevents water from entering, and the grass suffers because the water runs off.
Fertilizers applied on such soil can not enter and may be washed away in hard rain. Seeds that are sowed may germinate, but the tender roots cannot penetrate the crust, so seedlings perish. Oxygen, which roots need just as you and I do, is prevented from entering the soil.
The combined net effect is starvation, drought, and suffocation, truly good reasons why so many lawns are poor.
Weeds come in and often are blamed for “crowding out” the grass. However, the weeds are better suited to poor soil conditions. Change your conditions to suit the grass, which will “crowd out” the weeds.
Changing Soil Conditions
What can you do to improve what you have? We will try to simplify lawn maintenance, improve meals, and concentrate on practices with the greatest possibilities of producing results.
First, we should improve the physical conditions of the soil. Every gardener knows the value of a mellow, loamy soil well aerated for deep. Healthy root growth leads to more drought tolerance for the plant.
In a lawn, this desirable condition can be gradually accomplished by periodic cultivation and aeration (mechanical soil conditioning)—the deeper, sturdier roots which grow as the result of cultivation and eventually die.
Add organic matter to the soil and help to create mellowness. The soil plugs or cores are brought to the surface by aerifying help by top dressing the lawn.
Alternating wetting and drying inside the spooned-out holes is one of Nature’s best ways of creating better physical soil conditions.
Better air circulation in the soil greatly stimulates the unseen helpers—bacteria and other microorganisms—which improve the soil in many ways through their growth and death.
The increased oxygen supply in the soil also stimulates root growth and helps the roots to absorb more nutrients.
Add Some Lime
In the humid, high-rainfall areas of the country, soils tend to become acidic. Lime corrects acidity, makes nutrients available, and produces a more mellow soil condition.
Lime also granulates soils, which lets them breathe and improves them for most plants—except acid-loving plants, which do not include grass.
Home gardeners may choose between two forms of lime. Ground limestone is the safest for all-around home use, also called pulverized limestone and agricultural limestone. This form of lime is usually cheaper, too.
It does not burn the skin and can be safely used with all fertilizers and seeds. Hydrated lime, although faster acting. It isn’t easy to use.
It will burn sensitive skin and must not be used with fertilizers because it releases nitrogen as ammonia gas which burns foliage.
Good Time To Apply Lime
Fall is a very good time to apply ground limestone. One bag (80 pounds) of limestone to 1000 square feet is a good application that need not be repeated for three to four years. To use too much lime, or apply it too often, is about as bad as not using enough.
Verifying before liming is recommended so that soil improvement can be made in-depth instead of just at the surface.
Lime moves downward in the soil very slowly. Experiments have shown that aerifying greatly improves the penetration of slow-moving materials deeply into the root zone where they can do the best.
Physical soil conditions can be improved further by mixing such amendments as peat, sawdust, or sand into the soil—or a mixture of these.
Too often, these materials are spread on the surface of the lawn, where they defeat the very purpose they are intended to serve.
To be most effective, they must be thoroughly mixed into the soil. There are two ways to do this: First, destroy the lawn, plow it, or dig it up to mix the materials and start all over—mud, weeds, and all.
Second, spread the materials on the surface and mix by thoroughly aerifying, leaving the lawn intact without destroying the grass.
This practice is now used on many golf courses while maintaining excellent playing conditions. The second choice is wiser because the lawn can be used continuously and is much more economical.
The most economical way is to aerify, lime, fertilizer, and let the grassroots be the soil conditioner.
Fertilizing Lawns
The next step toward a good lawn is to improve the nutrient supply. Most lawns are poor because they are starved.
Well-fed grass will produce deeper, heavier roots which are Nature’s best soil conditioners. Therefore, indirectly, fertilizer acts as a soil conditioner by growing more organic matter. And, of course, it provides the elements necessary for healthy plant growth.
If you have either compacted clay soil or crusted sandy soil, fertilizer tends to lie on top of the soil where it has the best chance of being washed or blown away and the least chance of getting down deep into the soil where the roots can get it.
Acrifying to loosen and open the soil so fertilizer can reach the roots is standard practice on most golf courses and on many athletic fields today.
How Much Fertilizer
What fertilizer should you use this fall? That question will be asked many times all over the country.
There is understandable confusion because many kinds are available, ranging from everyday agricultural fertilizers to highly advertised ones. special “Turf Fertilizers.”
Soils differ, as do the requirements of various turf types of grass, so there can be no “universal” turf fertilizer.
For the lawn owner, the main features of a lawn fertilizer should be the long-lasting effect, safety from burning, and free-flowing and non-dusty texture.
Finally, high-nitrogen content could be named a fifth point because nitrogen is most important in producing dense turf.
A single annual application of a complete fertilizer can supply other nutrients (phosphorus and potash).
Here are a few examples of complete fertilizers, depending on your geographic location and available supply:
- 10-10-10
- 12-12-12
- 10-8-6
- 10-6-4
- 10-5-5
- 8-6-4
- 8-6-2
- 7-7-7
- 6-10-4
- 5-10-10
- 5-10-5
- 4-12-4
These fertilizers are best used once a year, either spring or fall, at a rate to supply one pound of nitrogen to 1000′ square feet.
Your dealer can inform you how much fertilizer will supply one pound of nitrogen.
You can figure it out for yourself, too. As an example, take a 10-6-4 fertilizer.
The first figure is nitrogen. 100 divided by 10 equals 10. It takes 10 pounds of 10-6-4 to yield one pound of nitrogen.
Another example is 5-10-10. The first figure is always nitrogen. 100 divided by 5 equals 20. It takes 20 pounds of 5-10-10 to yield one pound of nitrogen.
Straight Nitrogen
A lawn that has been fed 5-10-5 year after year probably suffers from acute nitrogen starvation and an overdose of phosphorous, the central figure.
The remedy for this is to use a straight nitrogen fertilizer for a couple of years at least. Organic nitrogen fertilizers are becoming more popular because they meet most of the requirements of a good lawn fertilizer.
There are several kinds on the market, some from sewerage wastes and some from plant and animal by-products.
The nitrogen content ranges from about 5% to 10% percent. Monthly applications of organic nitrogen fertilizers to yield one pound of nitrogen to 1000 square feet during the growing season are becoming standard practice in some areas, particularly when the lawn contains one or more of the improved varieties of grasses.
A new long-lasting, non-burning type of nitrogen fertilizer has been developed by chemically combining urea and formaldehyde.
Properly combined, the resultant product releases nitrogen slowly over a long period, similar in many respects to natural organic material. One of these will be on the market this fall.
Another nationally-advertised complete fertilizer, which has been on the market since 1955, contains a percentage of urea-formaldehyde ( U-F).
The cost is still high compared to natural organics, but the “no-odor” feature gives the U-F material a certain advantage.
Fall Seeding And Reseeding
Competition is a word that applies to lawns and the business world. In a starved lawn, the grass plants compete for the available nutrients.
Trees compete with grass (often unfairly) for sunlight, food, and water. In a new seeding, young grass plants compete with each other—survival of the fittest.
When seeding rates are very high, the surviving plants may be so weakened that they cannot compete with the weeds when the fresh seed is sown on an established lawn. Instead, the new seedlings must compete with the grass already there. Often, a thin lawn can be thickened and improved by feeding more easily and economically than reseeding.
One factor, more than any other, limits success in reseeding an old lawn. That factor is the seedbed. For instance, many lawns have been sodded with rough, weedy, ordinary pasture sod.
There may be some good grass, but probably very little. Reseeding is necessary. The usual practice is to scratch the soil with a steel rake.
In theory, the advice may be good, but it doesn’t produce results in practice. The seed will germinate, but the tender roots can not penetrate the dense, crusted, compact soil. As a result, they die.
Aerifying For Good Seeding
Aerifying is beneficial for fertilizing and watering and is just as good for seeding. A seed lodged in the loosened soil cavities is in the best possible position to germinate.
It can send its roots down into the moist soil below and produce a sturdy plant to add to the desired turf.
It has been demonstrated that with a proper seedbed, ‘ample nutrients, and adequate moisture, less seed will be needed to produce desired results.
New seedings should be mowed as soon as there is anything to mow. Frequent mowing is important with any grass. The more often you mow an established turf, the better it will be, other things being equal.
Removing Clippings
By all means, remove the clippings. Accumulated grass clippings create ideal conditions for disease organisms and insects. In addition, the return of fertility from decaying grass cuttings is too small to be significant on a lawn.
If the water company can spare any for use on grass, water should be applied generously at long intervals. Light.
Frequent sprinkling is a certain road to disaster. Good grass can wilt for several days without injury.
When soil becomes dry, it releases more plant food with the next watering, and it shrinks and cracks and lets air into the roots.
Occasional drying is good for soil and grass. However, if the water runs off into the gutter, it is time to verify again.
Basic Principles Of Lawn Management
The basic principles of lawn management discussed here apply to practically all lawn grasses everywhere.
My final advice is to suggest that each reader call their county agent and ask for the state college or university’s latest circular or bulletin on lawns. Such a publication will contain complete local information that could not be developed in an article like this.
Requests for lawn information support that phase of the university program and will assure you of better grasses and lawns in the future.
44659 by Dr. Fred V. Grau