Winter is a time when most people stop caring for their yard and lawn, it is however the correct time to fertilize, dethatch, and aerate. One extra step is of great help which is replacing beneficial bacteria. Fertilizer is a controversial topic and additional posts and articles will come later, for now I will only touch on organic natural fertilizer. The most common types are liquid and granular. Both are good and have their own pluses and minuses. Here at Texas Turf we use both types to ensure all the benefits of both are obtained.
FERTILIZING: A few of the biggest mistakes made when it comes to using fertilizers is not only using the right mixture, but using the right quantity and applying it at the right time of the year. Often times when spring comes around people feel as need to fertilize their lawns in hopes of seeing a green plush lawn as soon as possible. Too much fertilizer, especially with high levels of soluble nitrogen fertilizer, tends to increase thatch problems and leaver lawns more prone to insect and disease. Or, worse yet, you will literally burn your lawn.
Recommendation: The goal of a good fertility program is to produce a reasonable amount of top growth, but not at the expense of root growth or carbohydrate storage. A good root system is the key factor to a healthy lawn.
Nitrogen (N), Phosphorus (P), Potassium (K) Lawn fertilizers typically contain these tree nutrients, although other nutrients may be included in small amounts. The three numbers on the fertilizer bag represent the percentages of N, P and K in that order. The back of the fertilizer bag should show the guaranteed analysis. Always follow the recommended application rates suggested by the manufacturer on the bag. The grass plant needs more nitrogen than any other nutrient. Nitrogen is part of the chlorophyll molecule and helps give the lawn its deep green colour. Nitrogen also tends to promote high leaf growth rates at the expense of root growth. Phosphorus is responsible for the energy transfer systems in the plant and is generally required in much smaller amounts than nitrogen or potassium on an established lawn. The exception is for newly established lawns by seeding, sodding, or sprigging, when the need of phosphorus is higher in the new plant. Potassium has a lot to do with good cell wall development and the plant’s ability to withstand stress, disease and insect damage.
Look for slow-release forms of nitrogen. The two basic forms of nitrogen that can be used as a fertilizer are organic and inorganic. The most commonly used inorganic forms of nitrogen in fertilizers are ammonium nitrate and ammonium sulfate. Both are soluble, quickly available forms of nitrogen and both tend to produce a fast increase in leaf growth for a fairly short period of time. More and more, the slowly soluble or slow-release organic forms of nitrogen are being recommended by turfgrass experts. These include sulfur-coated urea, urea formaldehyde, I.B.D.U., methylene urea, natural organics, and resin-coated urea. These tend to produce a lawn with good colour without excessive leaf growth. They are designed to meter-out the nitrogen over a longer period of time. The slow-release forms of nitrogen do not have to be applied as often.
What fertilizer should I use? Most turfgrass experts recommend a lawn fertilizer should have at least one-half of its nitrogen in one of the slow-release forms mentioned above. In most cases, both Cool Season and Warm Season grasses will do well when a 3-1-2 or 4-1-2 ratio of N-P-K is used on an established lawn. Some analysis numbers that meet these ratios are: 12-4-8, 15-5-10, 16-4-8, 21-7-14 and 20-5-10.
How much fertilizer should I use? Fertilizer application rates should be as low as possible and still produce a high quality lawn. Over-fertilization weakens your lawn and causes excess leaf growth. As a general rule, if the amount of Nitrogen (N is the first number in the analysis) is between 5 and 12, the application rate should be 8 pounds per 1,000 square feet. Any N number over 19 should be applied at a rate of 4 pounds per 1,000 square feet. Always follow the recommended rate stated on the bag.
When should I fertilize? The best time to fertilize a lawn is when it is actively growing. For Nothern lawns (Cool Season grasses), begin the fertilization program as the grass begins to grow in the spring and reduce applications as the weather gets hotter. When cooler weather returns in the fall, the lawn can again be fertilized. A late fall fertilizer application after the first frost can increase lawn quality the following spring. For Cool Season grasses, it is usually best to concentrate a larger amount of nitrogen during the early fall growing period and a lesser amount in the spring. Southern lawns (Warm Season grasses), flourish during the warmer summer months, and therefore tend to require fertilizing shortly after green-up in the spring and again in the late summer months. For Warm Season grasses in southern areas, it is best to concentrate a larger amount of nitrogen during the early-late spring applications and a lesser amount in the fall. The fertilization program should start just after spring green-up and stop about two months before the average frost date in the fall. Frequency of fertilizer applications depends primarily on the amount and form of nitrogen used. The slow-release type fertilizers can adequately feed the lawn from 6 to 10 weeks. If the lawn still looks good and is growing well after 6 to 8 weeks, wait longer for the next application.
IMPORTANT: By leaving your grass clippings on the lawn you are adding nitrogen almost continually, which can reduce the need for fertilization by as much as 25%. And, leaving the clipping on the lawn (grasscycling) helps the environment by keeping clippings out of our community landfills.
DETHATCHING: Thatch is that tightly packed layer of dead and living shoots, stems, and roots that develop between turf or grass and the soil surface. As it is, dethatching takes a little time and effort and using the wrong dethatching equipment can make it a Herculean effort when it needn’t be. Some dethatching machines have flexible, leaf rake-type tines that are ineffective in removing thatch. Spring tines that attach to a rotary mower blade aren’t good for dethatching and can damage your mower. It’s important that you use the right equipment if you are going to dethatch. Don’t attempt to remove the entire thatch layer in one treatment and do not dethatch when soil is wet; only dethatch your lawn when it is needed rather than on a routine basis.
Recommendation: A little thatch is desirable, since it helps moderate temperature extremes at the soil surface and provides a cushion effect on the surface but too much thatch can present some negative consequences. To determine if your lawn has a thatch problem, remove a small, plug of turf several inches deep. Note the spongy layer of material between the turf and the soil. If this layer is more than ¾ to 1 inch thick when you compress it, you should consider having your lawn dethatched or begin a program which will encourage thatch decomposition. If you need to dethatch your lawn there are garden centres and equipment rental outlets that rent dethatchers. These machines are known as vertical mowers, verticutters, dethatchers or power rakes and they have vertically spinning blades which pull some of the material to the surface as they slice the thatch layer. Mechanical dethatching should be done in either late summer or fall when cool weather prevails. As is the rule when operating any equipment, follow the manufacturers or rental store’s operating procedures. The organic material dislodged by the dethatching machine should be removed and composted. It’s also important to note that grass clipping do not cause thatch and they are good for your lawn.
AERATION: Aerating a lawn is usually recommended when the soil becomes compacted and water and nutrients can’t get to the roots of the plant. Lawn aeration equipment will pull “cores or plugs of soil out of the ground, letting air in. These plugs should be 2”-3” in depth. Such a plug should be pulled out of the lawn at about every 3”. The plug-removal process is facilitated by watering the lawn the day before, but don’t water to the point of muddying the soil. One of the most frequently made mistakes is the lack of sufficient cores or plugs removed from the lawn. If the tines of the aerator are set more than three inches apart, and only one pass is taken on the lawn, the effort may not have been sufficient to solve the problem. Two passes may be required to ensure that air, water and nutrients can get down to the roots. Take care to mark all sprinkler heads so that they can be avoided with the aerator. This will save on costly repairs to the irrigation system.
Recommendation: Core aeration, a process where plugs of soil and grass are removed at regular intervals, can be done either by renting equipment or hiring a professional. A cool, dry fall day is the perfect time for this beneficial chore. Core aeration reduces compaction in heavy clay soils, permits a more rapid exchange of oxygen and water with grass roots and reduces the thatch layer on lawns. The soil and grass plugs can remain on the lawn since they will gradually decompose and return all their nutrients to the soil. Often times, two passes in the form of a crisscross pattern are recommended to make sure aeration is sufficient.
The type of grass will determine whether to aerify in the fall or in the summer. Lawns composed of Cool Season grasses such as Kentucky bluegrass and tall fescue are best areified in the fall, when there is less heat stress and danger of invasion by weedy annuals. Allow at least four weeks of good growing weather to help the plants recover.
Warm Season grasses such as zoysia grass, centipede grass, carpetgrass, St. Augustinegrass and bermudagrass, on the other hand, are best aerified in late spring and summer, when they are actively growing. With either type of grass, choose a day when temperatures are mild and soil is moderately moist, which makes the soil easier to penetrate. Avoid aerifying a wet soil, as it is messy and leads to further compaction of the soil as well. If the soil sticks to your shoes or if the core samples you take stick to your probe, you should wait until it dries out some before starting the job.
Bacteria and Mycelia (mushroom or fungus) spawn are an integral part of nature. Here at Texas Turf we have our own proprietary product and process for improving the soil and the nitrogen balance. Application of this product at any time of year ensures healthier grass and garden conditions exist in the soil. As a liquid mixture we spray the solution on to the soil and allow it to absorb. The magic happens just below the surface where UV light from the sun cannot reach it. The thicker the carpet of covering the better the result as the light is blocked more efficiently. Treating a yard twice a year can produce spectacular results. Winter is a time of less evaporation and a good time to prepare the soil for spring. It is highly recommended that grass and flower beds be treated so the results can be seen all Spring, Summer, and Fall.
I hope this short article has encouraged you to continue yard care through the winter and work with the dormant soil. You will be pleased with the results you get from the extra effort.