There are a number if things that impact the quality of your lawn. I focus on what I think is the most important, and the ones I can control. Aeration, De-Thatching and Overseeding or Renovation.
Aeration is one of the most beneficial activities you can do.
- Loosens compacted soil and increases the availability of water and nutrients.
- Enhances oxygen levels in the soil, which stimulates root growth and enhances the activity of thatch-decomposing organisms.
- While removing cores of soil, the spoons or tines also sever roots, rhizomes and stolons. Grass plants are stimulated to produce new shoots and roots that “fill up” the holes in the lawn and increase the density of the turf.
- Increases the lawn’s drought tolerance due to enhanced root growth and improves its overall health.
Thatch is a dense, spongy collection of living and dead grass stems and roots lying between the soil surface and grass plants on top. As a grass plant grows, the older sloughed-off plant matter from stolons (above-ground stems), roots, rhizomes (below-ground stems) and stems is often slow to decompose and begins to accumulate at the soil surface forming this thatch layer. Contrary to popular belief, grass clippings do not contribute to the thatch layer.
A shallow thatch layer up to ½ inch thick actually benefits the lawn, by helping to retain moisture and stabilizing soil temperature. A thatch layer greater than ½ inch thick makes watering difficult, since thatch dries out quickly and is difficult to rewet. Nutrients and water cannot be properly absorbed by the grass roots that tend to grow into this area.
De-Thatching- Vertical Mowing verses Power Raking:
The most common equipment uses an articulating blade (left) which does very little to remove thatch. It removes a lot of debris but that’s mostly material in the top surface. This is power raking. A vertical mower has straight fixed blades (right) with adjustable spacing and depth. The blades cut into the thatch layer and at least ½ inch into the soil. This along with Aeration is the most effective way to control the thatch layer.
Overseeding and Renovation
Overseeding can be done by hand in small areas. Larger ones require an Overseer. An Overseeder has fixed vertical mowing blades to cut down into the soil and then lays the seed into the cut. The added benefit of overseeding is that you are de-thatching at the same time.
Overseeding is very effective to fix damages areas or to renovate an entire lawn – depending on the original condition. If the soil is poor, new soil may need to be brought in. If there are too many weeds, they may need to be killed first.
all of these cultural activities are best performed late Summer into Fall.