Dethatching the lawn

http://www.bcnorth.ca/magazine/pages/Diana/lawn/lawn1.htm


Scarifying is done with your lawn mower. The regular cutting blade is replaced with a blade called a Roto-Rake. This is a flat blade with a spring and single tine on each end. This tine digs the thatch out of the lawn. Do not use a bag or chute on your mower, when scarifying. Put the plate over the opening as you would when mulching your lawn. Scarifying should only be done on a dry lawn. It should not be done on a lawn less than three years old.

Dethatching lawn with mower

The area to the left is covered with thatch

Before scarifying, check the depth of your blade. It should be touching the thatch, but not down so far that it would dig into the soil. Mow over a small area, then check to make sure it is not damaging the grass roots. Reset the depth if necessary. Once the depth is adjusted properly, keep mowing without stopping. Each time you stop, the tines tend to dig down too far, making a round trench in your lawn. When mowing with a dethatching blade, overlap the area you have already dethatched, to ensure that no strips are left. When rounding corners, be especially careful of this.