The best time to dethatch your lawn depends largely on your grass type and climate:
- For cool-season grasses (such as Kentucky bluegrass, fine fescue, perennial ryegrass), the ideal times are early spring (mid-April) or early fall (late August through September). These periods coincide with active grass growth, allowing the lawn to recover well from dethatching stress.
- For warm-season grasses (like Bermudagrass, St. Augustine, Zoysiagrass), the best time to dethatch is late spring through early summer (May through June). This matches the peak active growing period for these grasses. Avoid dethatching in extreme heat or drought conditions, which can stress the grass and hinder recovery.
- In transition zones with mixed grass types, dethatching time depends on the dominant grass. Cool-season dominant lawns should be dethatched in early fall, while warm-season lawns should be dethatched in late spring or early summer.
Additional advice includes dethatching when the soil is moist but not waterlogged and when the weather conditions support rapid turf recovery—moderate temperatures and avoiding stress periods like drought or heat waves. This timing ensures the dethatching process promotes healthier, thicker growth and reduces vulnerability to pests and diseases.
