Summer is a stressful time for home lawns. High temperatures and lack of moisture cause most lawns to go dormant for several weeks. Although this may look bad, it is a natural survival process and the grass will recover once weather conditions are more suitable for growth.
During this dormant period, the lawn is very susceptible to insect attack, weed invasion and wear injury. The lawn is unable to repair itself from all of this injury until it begins to grow again during the cooler, wetter conditions of late summer and early fall. Depending upon the extent and type of injury your lawn has suffered, there are several things which can be done in time for winter.
Hairy chinch bug and grubs are very common summer insect problems. Chinch bugs cause problems from June to August and should be treated when they are seen. Grubs are active during a shorter time, and should be treated in mid-August when the grubs are small and shallow in the soil. Lawns can withstand a certain population of these insects but begin to die rapidly once the numbers get out of hand.
When treating insect problems with insecticides make sure you use the products at the right rate and at the right time for effective control. The insecticide must come into contact with the insect in order to kill the pest. Most insects feed on the roots of the grass plants so the chemical must be placed at or beneath the thatch layer. This means that you should water appropriately before and after applying the insecticide application so that the chemical is washed down to the area where it is needed. Chinch bugs are shallow feeders and can generally be seen close to the soil surface. Grubs are often deep in the soil and require both heavier application rates and more water to wash the insecticide down.
Insectides are available as granular products in combination with fertilizers for safe and easy handling. The fertilizer will help to stimulate re-growth in the infected areas. For heavy populations, you should contact your local licensed lawn care company to spray the lawn.
Crabgrass, prostrate knotweed and creeping charlie are three examples of especially problematic weeds in summer. These are shallow- rooted plants which take over in bare patches of the lawn. Crabgrass seed will persist in the soil for many years, so if you know you have a crabgrass problem you may treat with a pre-emergent crabgrass control product early next spring. If you haven’t gotten it before it emerges, physically removing it is the only solution when it does appear. Non-grassy weeds, called broadleaf weeds, can be treated with a herbicide in late summer or early fall. Unlike insect control products, weed control products should not be applied in high summer since best control is achieved when the weeds are actively growing in late summer or early fall. Summer herbicide applications may also damage the grass.
Wear injury is caused by compaction and overuse of the lawn. Too many picnics under the shade tree may ultimately destroy the grass because the soil becomes compressed and the roots will suffocate. This can be repaired by aerating the lawn in early fall.
Grass begins to grow again in late summer since natural rainfall increases and temperatures are better for growth. This period of re-growth is the ideal time for re-seeding or sodding damaged areas of the lawn. There is plenty of time for this new grass to harden off before the winter.
When sowing seed in bare spots in an established lawn (this is called “over-seeding”) make sure there is soil-to-seed contact and that the seed does not dry out once it has been wetted. Choose a seed mixture which is appropriate for your site. Sun mixes for full sun, shade mixes for shade and a combination of both for sun\shade areas. Having the right type of grass is the first step in having a more successful lawn the following year. No matter whether it has been insects, weeds or general wear and tear, make sure you’ve dealt with the pest or you’ve repaired the soil before re-seeding or sodding the lawn. Apply a balanced fertilizer such as a 18-24-12 for newly seeded areas or a 12-8-16 for established lawns. The active root growth will readily pick up the applied nutrients and help the grass to recover rapidly so that you may enjoy it all through the fall.