Dethatching Your Lawn Is Part Of Fall

Thatch is a natural (and good) part of a healthy lawn since it provides nutrients to keep you lawn healthy. If you don't know what thatch is, it's the layer of grass clippings, small branches, twigs and seeds that have fallen on your lawn during the summer that accumulates at the bottom of the blades of grass lying just on top of the soil. A healthy layer of thatch should be about ½" thick and at that depth, it allows moisture to get through carrying nutrients down to the grass roots. 

However, over time thatch can build up and become much thicker than that healthy ½" (often as a result of letting grass grow too long before cutting), and thick thatch blocks moisture and nutrients from the roots and needs to be removed.

How can I tell how thick my lawn thatch is?

• If your lawn feels spongy when you walk on it, is usually a good sign of thatch build up. If that's how your lawn feels you can check further.
• Use a shovel or a long bladed knife and remove a piece of your lawn turf. You want to go down deep enough that when you lift up your turf sample, you can see a cross section of the turf, including the grass, thatch, roots and soil.
• Now you can visually check the depth of the thatch layer, If it's around ½' your lawn is fine, but if your have substantially more than ½" you should dethatch your lawn so it can grow healthy and strong. 
   

Dethatching your lawn

• Your first step should be to cut your lawn relatively short (about 1 ½"). This will make it easier to get that thatch up and out.
• While you can remove a thatch layer with vigorous raking, this is back breaking work and there are easier mechanical ways to do it.
• For example, you can buy blade attachments for your power lawnmower or consider renting a power rake or mechanical dethatcher at your local home store. Gardening experts suggest dethatching machines that use a series of blades to cut through the thatch and bring it up to the surface are less damaging to your lawn than dethatchers that use flexible rake like tines or the blade attachments. The cutting action prior to pulling is less likely to pull up patches of living grass and roots.
• No matter how the dethatcher works, you are going to end up with a large amount of debris on the surface of your lawn. You need to make sure to get that off the surface or it will end up acting just like a layer of wet leaves, blocking moisture and nutrients away from the roots. The good news now is getting rid of this uprooted thatch is relatively easy and can be done with a leaf rake (and lots of yard waste bags). 
   

Once you've got the thatch removed from your lawn is a great time to both fertilize and seed. The seeds will be able to get right into the ground and the fertilizer will give them (as well the rest of your lawn) lots of nutrients to grow green and healthy.

A word of caution. Some people feel that dethatching a job for the spring, not the fall. However, in the spring your lawn has just come through a long winter and the roots system and any new growth isn't as firmly established as in the fall, making it more likely that dethatching could harm your lawn rather than helping.

Murray Anderson is an experienced freelance writer over 500 articles published on the web as well as in print magazines and newspapers in both the United States and Canada. He writes on a wide range of topics and is a regular contributor to DoItYourself.com. He can be contacted at murand@lycos.com.