How to Overseed Hay

Look for dormancy in growth of grasses or legumes during the fall season. Exact times depend on geography and weather. Continued growth of existing vegetation will limit that of the new seeds. At the same time, overseeding must be initiated as soon as dormancy can be confirmed, or the new seeds will have insufficient time to develop.

Mow the dormant grasses down to about 1 inch in height, or else let the livestock graze until you have stubble of that length. New seed thrives better in short grass.

Sample the soil with a soil pH test kit before planting new seed, especially if you over seed with legumes. Acidic levels should exceed .60 for most clovers and reach 6.6 for alfalfa. Grasses favor pH range of 6.2 to 6.9.

Spread the new seed with a broadcast seed spreader attachment. Calibrating the amount per acre depends on the seed. Arrowleaf clover, for example, works with five to eight lbs. per acre. Crimson clover, on the other hand, can call for up to 20 lbs. per acre. Consult your seed dealer or extension agent for guidance in this area.

Fertilize the hay field shortly after dropping the seed. Apply phosphorous and potassium without delay. The exact amount of nitrogen depends on the results of the soil test. Subsequent applications should take place in late winter and spring.

Rotate the livestock for grazing the field. This increases the contact between seed and soil. It further eliminates any residual growth from the original vegetation.