Contractor's Mix contains annual ryegrass so it germinates quickly and provides a fast grass cover. It is most often used by new home builders to establish a lawn quickly because it provides excellent value for the price. Contractor's Grass Seed Mixture can be overseeded with any Black Beauty Grass Seed Mixture to grow a lawn that will persist for years to come. It's easy to grow and maintain, and it's resistant to both heat and cold.