Turf grasses usually grow in base or alkaline soils. Heavily acidic soils can interfere with the ability of grass roots to take up nutrition. Soils heavy in acid also can affect the types and amounts of minerals in the soil. Adding lime to soil is an effective way to "sweeten" it so lawns are healthier. Lime is just crushed or ground mined limestone. It will increase the calcium and magnesium in the soil, which will increase iron uptake.
Ideally you should have your soil tested prior to laying sod or seeding. This can help determine the type of grass you should install, as each grass type has different pH requirements. Failing that, you can still take a soil sample to your county extension or a nursery and get it analyzed. If it is found the soil is too acidic, add lime to raise the pH and lower the acidity. Keep soil pH for turf between 5.8 and 7.0.
Lime is a soil amendment that neutralizes soil acidity, enhances soil tilth, stimulates microbes, enhances nutrient uptake and adds calcium and magnesium. Calcium is a regulator; it aids in bringing the correct amount of certain nutrients to the plant. Lime acts as a regulator for zinc, copper and phosphorus. In addition, it reduces the toxicity of aluminum, manganese and iron which otherwise could harm plant growth over time. Once the soil is sweetened, the ability of plant roots to uptake proper nutrition is enhanced and soil condition is improved.
Pelletized Calcite or Dolomite Lime
There are two main kinds of lime used in agriculture. Calcite lime contains calcium carbonate but little magnesium. Dolomite lime contains both minerals in high concentration. Pelletized lime is simply crushed lime aggregated into larger pieces to make it easier to spread. It is easier to apply than crushed lime and better for your lungs. It is also more expensive, but when applied according to instructions it works equally as well. Pelletized lime changes acidity as fast as hydrated lime and much faster than ground or dolomitic lime.
You can apply lime any time of the year. Fall is the best time, as the lime will have time to work into the soil by the spring. It is best not to apply lime at the same time as fertilizer, as they tend to neutralize each other. Apply them several weeks apart. Wash lime off the grass blades to prevent burning. Lime needs to get into the soil to work, so aeration prior to application is a good way to ensure that it can penetrate thick thatch and roots.
You can spread lime with a rotary spreader. Spread it evenly to avoid over-liming. Incorporate it into the soil with rotary tilling. This enables you to apply the lime in one application. You can also administer it after thatching and herbicide treatments, and before or after aeration. The lime pellets will fall into aeration holes and mix better into soil. A general rule of thumb for established turf is to spread 25 to 50 pounds of lime per 1,000 square feet.You can spread the applications out over time to avoid concentrations of lime in the soil and associated plant damage.