Will Grass Grow Where Moss Has Grown?

Soil pH Test

• Grass grown outside of its preferred pH range cannot absorb the soil's nutrients. When the soil has a pH range between 6.0 to 7.0, all of the nutrients grass needs for healthy growth and spreading are available for absorption through the root system. Moss thrives when the soil is too acidic, so making the soil more alkaline prevents moss growth and allows grass to spread easily. To test your soil, dig a 6-inch hole in the lawn. Collect soil from the bottom of the hole and follow the directions on a soil pH test. You should then spread dolomite limestone to raise the pH range.

Liming

• The amount of lime you apply on your yard depends on your existing pH range. For a pH range between 5.0 to 5.5, spread 100 lb. of limestone per 1,000 square feet, as suggested by Cornell University. Break up the limestone applications and apply 50 lb. in the spring and 50 lb. in the fall. Those with a soil pH range between 5.6 to 6.0 should spread 50 lb. of limestone per 1,000 square feet.

Thatch

• Typically, moss grows on lawns with underlining thatch problems. Thatch is the buildup of both living and dead organic material between the grass and soil. This thatch layer creates an environment for moss growth. Also, gardeners should remove their thatch in order to seed their lawns. Check your thatch layer by cutting a 2-inch square of turf out of the lawn and measuring the thatch layer. Dethatch the lawn with a power dethatcher if you have a thatch layer over 1/2 inch.

Watering

• Moss thrives in moist soils and lawns. It is important for gardeners to avoid overwatering their new grass to prevent future lawn problems. Lawns need 1 inch of water a week. You can tell how much water your lawn has received by placing a tuna can out in the lawn. A tuna can is 2 inches tall; therefore, a can that is halfway full of water means the yard needs no additional water. If it is less than halfway full, supplement the water for the lawn.