How to Cure Thatch
Thatch is a layer of organic materials (such as decomposing grass, roots and leaves) that forms on the surface of the soil. Don't worry about thatch if its thickness doesn't exceed 1/2 inch. A thicker layer will prevent the grass roots from reaching the soil, however, which can result in patches of dead grass throughout the lawn. Thatch also prevents water and nutrients in fertilizers from reaching the soil, and promotes fungal and insect infestations. There are a number of measures you can take to cure thatch.
- Difficulty:
- Moderately Challenging
Instructions
Things You'll Need
- Lawn mower
- Spading fork
- Ruler or tape measure
- Dethatching rake
- Power dethatcher
- Leaf rake
- Liquid fertilizers
- Aeration tool
- pH testing kit
- "Prilled" or granular limestone
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Dethatching
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1
Mow your lawn to half its normal height.
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2
Remove a small piece of turf from the lawn using a spading fork and measure the thickness of the thatch.
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3
Loosen the thatch without removing the grass, using a dethatching rake (in case the thatch layer is not thicker than 1 inch).
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4
Loosen thatch thicker than 1 inch by using a power dethatcher. If you're not experienced with dethatching machines, it's best to hire a professional.
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5
Use a leaf rake to collect all the thatch and add it to your compost heap.
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6
Apply liquid fertilizers to the lawn after dethatching. Liquid fertilizers don't get trapped in the thatch. They promote natural decomposition of the thatch by improving nitrogen levels in the soil.
Aeration and Liming
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1
Remove plugs (about 3 to 4 inches deep) of grass and soil throughout your lawn, using an aeration tool. Aeration allows water, air and nutrients to reach the soil and exposes the thatch to the bacteria needed for decomposition.
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2
Leave the plugs on the lawn; they will disintegrate into the soil in two to three weeks.
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3
Check the pH level of your soil. Take a soil sample to a garden store for testing or use a pH testing kit. If the soil is too acidic, it will slow down the natural decomposition process and cause thatch buildup.
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4
Sprinkle "prilled" or granular limestone on the surface of the lawn to neutralize the acidity level of the soil.
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1
Tips & Warnings
The best time for dethatching and aeration is the early fall or spring. It's best to aerate the lawn once or twice a year to prevent the buildup of thatch.
You can apply lime on the lawn at any time throughout the year.
Don't overwater or overfertilize the lawn; both will promote thatch growth.
Dethatching is a stressful experience for the lawn; it won't look pretty after you're done. It may take a few weeks for your lawn to regain its appearance.
