Vernalization is required for collards to bolt (become reproductive) therefore planting anytime during the growing season will result in pure vegetative growth. Vernalization is a prolonged cold special that triggers a species genetic code within the plant to start reproducing. This is important because the longer a species stays in the vegatative stage, the more total biomass production potential. In fact you could plant collards in the spring and it they will continue to grow through that next spring before trying to reproduce. Collards growing point is protected close to the surface making for excellent regrowth potential after grazing. Premium forage produced by collard ranks it above many other options on the current market place in CP and digestibility.