You’re doing all the right things for your lawn: it is properly mowed, fertilized and watered.You have even made arrangements for insect and disease management. So how come your lawn still doesn’t look as green, thick and healthy as you would like?
A culprit that is often overlooked is soil compaction. When the top four inches of soil are compressed, grass roots are not able to get the essential elements they need. This stresses the plants, makes them less competitive with weeds and less resistant to injury. Lower oxygen levels in highly compacted soil also prevent earthworms and other organisms from reducing thatch, which is associated with severe maintenance and pest problems.
The simple solution to soil compaction and thatch buildup is core aeration, a process of removing plugs of soil to penetrate thatch and improve the flow of air, water and nutrients to grass roots. Deeper roots and a denser, healthier lawn will result. An added bonus is increased tolerance to drought and reduced water runoff and usage.
Following aeration is the ideal time to revive your lawn with overseeding, since the core holes and soil resulting from aeration create spots for seeds to germinate. Introducing new seed varieties to an existing lawn is one of the most effective ways to enhance the quality of your lawn. Aging grass does not produce new stems or tillers as rapidly as young grass. In addition, lawn installed years ago can’t compare with the benefits of today’s improved grass seed which adapts better to changing landscape conditions. Not only can new seed varieties help protect a lawn from drought, disease, pests, excessive traffic and shade; but some also require less fertilizer, technical materials and water.
If your lawn is extremely weak with a majority of unhealthy turf, slice seeding is needed. In this case, a machine creates slits in the lawn allowing seeds to drop directly into the soil, maximizing the success rate of germination. Slice seeding is used in a complete lawn renovation and for touch-ups of bare areas.
Whether you decide to aerate and overseed, slice seed, or both, it is critical to keep soil moist until the new seeds germinate. Avoid foot and pet traffic and mow very carefully so as not to disturb new grass plants. After seed germination, water less frequently but more deeply to encourage deeper root growth.
Fall is the best time for aeration and overseeding, when conditions are most favorable for new cool season grass seedlings to become established before colder temperatures arrive.