Moss in lawns is a sign of poor growing conditions. These conditions can range from not enough sunlight to soil not being suitable for certain types of grass species. Lawns that retain moisture, or hold water on the surface, may be the most vulnerable for growing moss instead of grass. While there are variable conditions for moss growth in a lawn, there are a number of steps homeowners can perform to eradicate this moisture-loving and shade-loving plant.
Conduct a soil test from several areas around the lawn where the moss growth is the greatest. Contact your local agricultural extension service for methods and processes concerning soil samples and locations. The test results will be back in your hands in approximately six weeks.
Aerate the soil using a mechanical lawn aerator. Typically these machines can be rented from your local equipment rental agency. The mechanical aerator will remove small plugs from the soil and redeposit the dirt plugs back onto the top layer of grass. The aerator will create small drainage holes in the soil. Mechanical aerators will also perform the task of de-thatching the lawn. Thatch is the dead grass and other debris that collects on the soil surface just under the blades of grass.
Apply the recommended strength and amount of fertilizer as specified by the soil test. The chemical fertilizer will immediately begin to increase vigor to the existing grass and lawn. Vigorously growing lawns will cause competition not only for the moss, but for any weeds that may be taking hold as well.
Broadcast and water into the soil the recommended amount of agricultural lime. Raising the soil pH level between 6.0 and 6.5 will benefit the grass turf in the long run. Adding lime will not immediately affect the growth of the moss.
Reseed the lawn with specified grass seed for your particular location. Various soil conditions and shaded lawns will require the application of a specific grass species. The agricultural extension service will have recommendations for the soil type and climate conditions of your area.
Add organic material to your lawn in late fall to early spring to increase drainage of the lawn. These organic materials will include well composted organic matter, humus and topsoil.