Frost seeding is an economical method of improving pasture and hay fields by broadcasting the seed on frozen ground. As the ground freezes and thaws, it opens and closes allowing the seed to be incorporated into the soil. This keeps the seed from germinating until there is a good moisture supply early in the spring. Legumes are the most successful for this system as they tend to be rounded, dense and most importantly, they germinate at lower temperatures so will begin growth early in the spring.