In the world of professional sport turf management thatch is well talked about subject, less however when it comes to home lawns. Excessive thatch is one of the main reasons a lawn will require a renovation. Thatch is the layer of organic matter layer that sits between grass surface and the soil, thatch is the decomposed and undecomposed organic matter produced by the grass itself. Thatch accumulates naturally as turf grows, generally the faster a grass species grows, the quicker thatch can accumulate. This can be magnified through high inputs such as excessive watering and high fertiliser inputs. You may remember walking over a lawn that feels spongy under foot? That’s the excessive thatch layer you can feel. Sometimes considered somewhat good in a lawn environment because of the soft feel it can bring to a lawn while also increasing the wear tolerance of the lawn, however, we don’t like the thatch layer becoming too excessive in a lawn because;
- It holds more moisture than the soil itself, meaning grass roots prefer to live in the thatch rather than grow deep into the soil. Resulting in your lawn drying out faster during hot weather.
- It increases the likeliness’ that insect and disease will become a problem
- As its soft in nature, it increases the chances of the mower sinking down in the thatch layer and scalping as a result making the lawn present poorly.
- It slows the rate your lawn will drain as water moves through it slowly.
- It prevents fertiliser from entering the soil profile to encourage the roots to grow deep
What are the ways to reduce thatch?
- Scarifying
- Aeration
- Sand topdressing
- Select grasses that produce less thatch
- Restrict fertiliser, especially nitrogen
- Reduce water inputs, only water your lawn when it really needs it
