On beautiful sunny spring days, many of us enjoy working on our lawns. If yours needs improvement, here are some suggestions. First, assess the condition of your lawn.
· Do you have a thick stand of turf or do you have thinning areas or bare spots?
· Are weeds a problem?
· Does your lawn have thatch?
· Are insects or grubs invading your lawn?
· Does your lawn have any disease problems?
· Do you have the proper soil pH?
When over-seeding, the most important thing to remember is to obtain good seed-to-soil contact by working up the soil in the area to be seeded. Sow the seed at the recommended application rate and lightly cover with soil. Then cover with clean straw. Water thoroughly, but do not over-water to the point of run-off. Keep the seeded area moist during the germination period and never allow it to dry out.
Thatch is not just a collection of grass clippings caught between blades of grass. It is primarily grass root stolons and rhizomes. In a healthy lawn, earthworms and soil microorganisms break down the thatch naturally. Thatch is a symptom of shallow watering and chemical fertilizer usage.
The dead roots in thatch have a high concentration of lignin, a fibrous material that is very resistant to decomposing. Thatch is a great environment for pathogens (disease-carrying agents) and harmful insects. Thatch inhibits good absorption of water and nutrients by the root system. Because thatch is not very permeable to water, much of the rain runs off and the soil below stays dry.
Prolonged and frequent use of chemical fertilizers makes your soil inhospitable to worms and other beneficial soil critters. Frequent shallow watering causes grass roots to grow at the top ½" of soil, creating ever thicker layers of thatch.
A thin thatch layer is okay – it acts almost like a mulch – but when it gets thicker than ½", it suppresses growth of grass, keeps water from penetrating into the soil, and becomes a perfect medium for fungus. Bluegrass is more prone to develop a thick thatch layer than other grasses.
What to do? Rent a power detacher to pull up the tough, tangled thatch. (Early fall is the best time to do it; springtime is okay, too.) Stop using chemical fertilizers. In dry weather, water long and deeply. Mow often, and cut off no more than ⅓ of the blade; mow high, so grass is about 3" high.
How do you tell if you have thatch? Using a spade or knife cut a 3" deep plug or sample from a typical lawn area. Examine the sample for a brown to yellow-tan layer, starting at the base of the grass stems. There will be little soil in this layer, just a dense tangle of roots. If your lawn is bluegrass, if your lawn was started from sod, or if you use chemical fertilizer, you almost certainly have thatch.
Watering too little or too often encourages grass roots at the soil surface, which adds to the thatch layer and makes roots susceptible to drought.
When you walk on your grass it normally springs back quickly. Wait until the color seems a little dull and the grass does not spring back so quickly – that's usually the right time to water. Apply about an inch of water that will penetrate the top 6"-8" of your soil.
Eliminating thatch is the best way to get rid of insects that damage the top growth of your lawn. Beetle grubs, however, feed on your grass roots from below the soil surface. Grub damage appears as dead or dying patches in the lawn. If you grab the grass in your hand, it will pull up like a carpet; there are no roots holding the turf down anymore. Grub-Away™ Nematodes are the best method to eliminate grubs in your lawn. Mixed with water and sprayed or sprinkled with a watering can, these microscopic "eel-worms" will search out the grubs in your lawn, invade their bodies (killing them) and reproduce in the decaying grub body. This process continues until freezing temperatures kill-off the nematodes.
For common lawn diseases, prevention is the key. Besides following the recommendations given above, other preventive measures you can take are:
a) Use disease resistant grass seed.
b) Prune trees and shrubs to allow more light and air to reach the grass.
c) Water in the morning, so that grass blades dry before nightfall.
Your soil can be rich in nutrients, yet produce very poor plant growth. For example, if pH is too high (alkaline), plants can't efficiently absorb iron, copper and zinc. Most plants, including grass, do best if soil pH is between 6 and 7. Once your soil pH is determined, it's easy to adjust. Your local County Extension Office can help you make this determination and advise you on how to adjust your pH, if necessary.
Following these practices should result in a beautiful healthy lawn.