What Do I Add to Clay Soil to Plant Grass?

Manure

• The idea of handling the excrement of animals may seem gross, but pull on those gloves. Not only does manure help recondition the soil and improve the aeration of clay soils, it also provides high levels of slow-release nitrogen that can help feed your grass over several months. For sufficient clay modification, use 1 to 1.5 cubic yards of manure for every 500 square feet of lawn space. After spreading the manure, mix it thoroughly into the top 4 to 6 inches of soil.

Peat

• Dried peat moss, sold by the bale in landscaping and garden stores, isn't just good for mulch and decoration. It also helps enhance heavy clay soils by separating the compact clay particles for better movement of both moisture and oxygen. For satisfactory results, apply peat at a rate of 1 cubic yard for every 500 square feet of lawn topsoil. Once applied, mix the peat into the top 6 inches of dirt.

Compost

• Compost, whether it's homemade in your backyard or purchased commercially as a finished product, has multiple uses in the outdoor landscape. Not only does it turn green waste into potent plant feed, but its organic particles also recondition clay soils for improved aeration. Spread 3 to 4 inches of finished compost onto your lawn topsoil, then mix it 6 inches into the dirt.

Limestone and Fertilizer

• After aerating and improving the compact nature of your clay soil, it's time to adjust the clay's pH levels and nutrient levels to foster proper grass development and establishment. In most cases, using 25 lbs. of dolomitic limestone for every 500 square feet of lawn space works. After spreading the limestone, use a general all-purpose lawn starter fertilizer like a 18-24-6 or a 10-20-10 product, administered at the rate suggested on the individual fertilizer's label.