Dethatch cool-season lawns in early spring if needed

If thatch exceeds three-quarters of an inch on a cool-season lawn, dethatch in early to mid-spring (April) when the grass is actively growing. Use a power dethatcher or dethatching rake.

Why It Works

Dethatching during active growth gives the lawn maximum recovery time. Cool-season grasses grow vigorously in spring, quickly filling in any damage from the dethatching process.

Tips

• Early fall is actually the preferred time to dethatch cool-season grasses — spring is the second-best option.
• Dethatch warm-season lawns in late spring to early summer after green-up, never in early spring when they are still dormant.
• Mow slightly lower than normal before dethatching, then return to regular height.