What Is Thatch?

Thatch is composed of a tightly intermingled layer of stems, leaves and grass roots, which accumulates between the vegetation and the soil. Too much thatch increases the turf’s susceptibility to diseases, reduces its tolerance to drought, cold, and heat; and hinders the movement of air, water, fertilizers, and nutrients into the soil. In severe cases roots of the grass will not grow into the soil but actually take root in the thatch layer making the turf susceptible to drought and heat stress. Thatch will accumulate if the production of dead material exceeds the ability of the microorganisms to break down the material into elemental components. Thatch build-up increases during poor soil aeration and drainage, cold soils, the use of some pesticides, and the excessive use of fast release nitrogen fertilizers especially in a water-soluble form (Controlling Turf grass Pests). Using non-organic or fast release fertilizers inhibit microorganism activity, which helps decompose thatch. When a thatch layer is greater than 3/4 of an inch thick it may need to be physically removed. The best way to quickly repair a thatch problem is by power raking the lawn or physically removing the thatch layer. To prevent major damage power raking must be performed before the lawn greens up. When a severe thatch layer is discovered after the lawn has already greened-up than the thatch should be controlled through an increase of microbial activity and/or a reduction of the growth rate of the turf. The best methods of increasing microbial activity in the soil is by using only organic fertilizers, core aerating, and by adding a microorganism stimulant like Revive.

Thatch Preventative Practice

Mowing – Never cut more than 1/3 of the blade of grass at one time. Mulching does not increase the tendency to build thatch. Change the mowing height to 2.5 inches in the spring and fall and increase the height to 3 inches in the summer.

Fertilizing – Fast release nitrogen applications will result in a decrease in thatch decomposition and an increase in thatch production rates. Always avoid high dosages of synthetic nitrogen sources like ammonium nitrate and urea.

Irrigation – Avoid light and frequent watering. Always irrigate the turf deeply and infrequently. This entices the roots of the grass to grow deep into the soil instead of the thatch layer.

Pesticide – Pesticides negatively affect desirable microorganism and earthworm populations. Pesticides should be avoided unless absolutely necessary.

Power Raking is great a way to remove the dead debris and crust that builds up on a lawn over winter. It is also a gentle way to remove thatch from the lawn without causing the significant damage that dethatching can cause. We recommend power raking in the early spring before new growth has begun. Power raking slices the surface stolons and stimulates new growth, thickening the lawn.

Power Raking in Colorado Springs can be done in the spring or fall. If you are power raking to remove winter debris it is recommended to do it before the lawn starts growing to avoid setting the lawn back during the critical spring time growth. If power raking is being combined with over seeding we recommend doing it early spring to allow the new seedling plenty of time to get established before the summer drought and heat. Late summer/early fall remains the optimum time for any over seeding because you avoid the summer heat and drought and the new seedling do not have to compete with the spring germinating weeds.

Power raking is seen as an easier and more efficient option than dethatching. Because the blades only cut the surface of the grass, it aerates the lawn and helps get rid of dead matter without destroying the healthy grass. Dethatching is a much more extensive process that can tear apart growing grasses and needs to be followed by careful care of the lawn. Power raking targets only the dead grass layer and when done effectively, removes waste without causing damage so that the lawn can heal quickly and no permanent damage is done.

Why Lawn Pros? We continue to strive to be the best we can be. We invest in our people and equipment. We don’t look for short cuts. We continue to look for the best way to service our customers. We use only the best products.


Lawn Pros
(719) 963-6267

3335 Landmark lane Colorado Springs CO 80910

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