Moss problems are attributable to poor drainage, shade, wrong pH, but more than likely low soil nutrient levels. White clover and Heal-all are good indicators of low soil nutrients.An annual fertilization program is needed to maintain a lawn in healthy condition, for no other area is subject to such continuous leaching away of plant nutrients.
When the soil is reasonably dry in late February to early March or at least before the first cut, rake the lawn to remove any accumulated winter junk, followed by de-thatching and aeration. Then apply 15 to 20 lbs per 1000 square feet of Dolopril, a fast acting 20% Calcium and 11% Magnesium ground limestone in prilled form, making it easy to apply. By late March or early April apply a balanced lawn fertilizer.
Lawn rolling should be left until May, when worm castings have slowed down and soil is just moist. Rolling a wet lawn will do more harm than good. It will actually compact it.
If there is a real moss presence in the lawn, usually caused by low soil fertility, spread Ammonium Sulphate (21-0-0) on the lawn at the rate of 10 lbs per 1000 square feet, and don’t wash it in. It will burn out the moss and will burn the grass to some extent, but the grass will recover in 2 to 3 weeks.
Fertilizer requirements will vary, depending on the soil fertility and the amount of rainfall or watering of the lawn. Generally speaking it may be determined by the color of the grass. With another half rate application in June and a full application in August should keep your lawn in good condition.