Lawn Cultural Practices That Prevent Thatch
Lawn Mowing - Never cut more than 1/3 of the blade of grass at one time. Mulching the grass clippings 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 or taller in the summer.
Lawn Fertilizing - Fast release nitrogen lawn care 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 because they are salt based and kill beneficial microbes. Organic fertilizers stimulate beneficial microbial activity in the soil.
Lawn 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. The lawn may look worse for a few weeks, but deep and infrequent watering will stimulate the roots to establish into the soil instead of the thatch.
Lawn Pesticide - Pesticides negatively affect desirable microorganism and earthworm populations. Lawn care pesticides should be avoided unless absolutely necessary.