Medicago sativa Released in 1953, Vernal remains a very winter-hardy variety even in the most northern climates. At maturity, alfalfa can produce a huge amount of green biomass capable of putting back up to 10 tons per acre into the soil at plowdown. Generates 150-250 pounds of nitrogen per acre and also serves as a great forage crop for animals. Thrives in well-drained soils with a pH above 6.0. In gardens, prepare as you would a lawn with a fine and firm seed bed. The seed prefers good soil contact; sow about 1/4-1/2 inch. Roll with a lawn roller. Can be spring or late summer sown. You must plant 6-8 weeks before the first killing frost in the late summer to allow good establishment going into winter. Great for sowing between crop rotations as a high nitrogen producing cover crop. Recommended seeding rate: 1/2 pound per 1000 square feet; 15-20 pounds per acre. Pre-inoculated.