The best time to remove thatch is when your lawn is thriving in the spring or fall. You must expose the soil between the old grass plants and remove weed colonies using a power dethatching rake or there are manual dethatching rakes also. Removing thatch might reveal uneven areas in your lawn. Read how to fill depressions and level bumps prior to completing this process.
Should you dethatch before or after moving?
You’re going to want to mow before you dethatch. When you’re ready to start removing thatch, begin by setting the height adjustment on your mower to cut the grass to about half its normal mowing height—and mow the entire lawn. Short grass will make dethatching and surface preparation easier. It will also improve seed germination rates because more seed will make contact with the soil and seedlings will have better exposure to the sun.
Before you start to remove thatch using a de-thatcher throughout your lawn, make several test passes on an inconspicuous area of your lawn to see how much thatch (and turf) is removed and adjust the blades height accordingly.
When using a dethatching blade on a mower to dethatch, make several passes over the lawn in perpendicular directions. It is important to be thorough. Remove the thatch that you pull up after each series of passes, and add it to your compost pile. When you have finished dethatching, re-mow your lawn removing any loose thatch.
Removing Thick Thatch
On a lawn with very thick thatch (more than 1-½ inches), you may need to partially remove the thatch and allow the lawn to fully recover before the next dethatching session. Removing too much thatch all at once can do more harm than good. The rule of thumb is to remove thatch as much as you can without tearing up holes of more than a couple of square inches in live turf.
Dethatching for Large Lawns
The easiest way to remove thatch from a lawn that is more than 3,000-square feet is by using a power rake, or a mower with a dethatching blade (a machine with vertical instead of horizontal cutting blades), which should be available at rental stores.
Dethatching for Small Lawns
For smaller lawns or lawns with thin layers of thatch (½- to 1-inch), a manual de-thatching rake will do a satisfactory job.
Does Dethatching Remove Weeds?
Before you remove thatch, weed your lawn. The process of removing thatch won’t remove weeds in your lawn, so take care of the mature weeds first, but it might have direct effects on weed growth in the future. How so? Dethatching your lawn gives your grass access to more oxygen and allows nutrients to get to the grasses’ roots, giving your grass the upper hand when any weeds try to edge their way in. Removing thatch also removes the habitat for many different types of fungi that can cause spotting and disease in your lawn.
