Power Raking / De-Thatching
Thatch in lawns is often misunderstood; both its cause and control. Some lawns have serious thatch problems while others do not. Thatch is a layer of living and dead organic matter that occurs between the green matter and the soil surface. Excessive thatch (over 1/2 inch thick) creates a favorable environment for pests and disease, an unfavorable growing environment for grass roots, and can interfere with some lawn care practices.
What is thatch?
The primary component of thatch is turfgrass stems and roots. It accumulates as these plant parts buildup faster than they breakdown. Thatch problems are due to a combination of biological, cultural, and environmental factors. Cultural practices can have a big impact on thatch. For example, heavy nitrogen fertilizer applications or frequent overwatering contribute to thatch, because they cause the lawn to grow excessively fast. Avoid over fertilizing and over watering. Despite popular belief, short clippings dropped on the lawn after mowing are not the cause of thatch buildup. Clippings are very high in water content and breakdown rapidly when returned to lawns after mowing, assuming lawns are mowed on a regular basis (not removing more than one-third of the leaf blade).
Thatch sheds water, preventing its infiltration and creating localized dry spots. This can be a serious problem especially on slopes and south and west exposures. Thatch can minimize the movement of air and fertilizers into the soil layer weakening the turf and making it more susceptible to insect and disease problems. However, a moderate level of one-quarter to one-half inch thickness can be beneficial as it makes grass more tolerant to wear, soil is less susceptible to compaction due to the crushing effect and acts as a mulch preventing accelerated drying of the soils surface.
Used properly, power raking turf can speed spring green-up by letting air move into the root zone and warm the turf.
It is recommended to dethatch when the thatch layer is 1/2 inch thick or more. You can check this by cutting a plug out of the grass and measuring the thatch layer. If the thatch layer is less than 1/2 inch thick, then a lawn aeration would be more beneficial.
The best months to dethatch in Colorado Springs and the surrounding areas is March – April before grass gets too green.