Lime Fertilizer

Excessive rainfall leaches ions such as calcium and magnesium from the soil, creating an acidic condition in the soil. These elements help the soil pH stay neutral. Lime fertilizer brings the pH back to a normal level when acidic conditions occur. The optimum pH for turf growth is 6.2 to 6.5. When an acidic condition occurs, the pH falls below 6.0. Turf growth is adversely affected when the pH falls below 5.5. Spreading lime on the turf is an important part of turf management in the eastern United States due to the amount of rain that falls and the high humidity.

When to Apply Lime Fertilizer

Because lime can have an adverse reaction on the turf if the soil is not acidic, lime should only be applied after a soil test is done and the soil test shows an acidic condition. Lime comes in two different forms: powder form and pelleted form. Lime is non-toxic to humans and pets and does not cause pollution.

How to Apply Lime Fertilizer

When applying lime fertilizer, uniform coverage is important. Use a drop spreader or a spinner spreader to ensure uniformity. Lime is insoluble and will stay where it is spread. If an area of lawn is missed, it will not receive the lime needed to neutralize the acidic condition. If the lime is overlapped, the overlapped areas will have too high of a pH level, which may cause trace element issues. When spreading, spread half of the lime in one direction (north to south), then the other half in the other direction (east to west).

When spreading the lime fertilizer, it is important to follow the instructions on the package. If the application calls for 50 pounds per 1,000 square feet, use 25 pounds in the north-south direction and the other 25 pounds in the east-west direction.

Lime can be applied at any time if needed, but the best time to apply lime fertilizer is in the fall. Applying lime in the fall allows the material to break down over the winter, making the soil ready for the next season’s growth. If urea fertilizer is used in conjunction with lime, be sure to apply the urea fertilizer at least three weeks prior to spreading the lime. This will give the urea time to react with the soil. If urea fertilizer is applied at the same time as the lime, the nitrogen in the urea fertilizer will be negated because of the increased pH around the fertilizer granules.