Certified GKH Gardening Expert
Alfalfa plants adapt fairly easy to most climate and soil conditions but to answer your questions:
1. Cool-season simply means the plants typically grow better in cooler conditions during spring and fall, such as the northernmost states in the U.S. That is not to say, however, that alfalfa cannot be grown in other areas like the South.
2. As for the soil, alfalfa prefers soil that is deep and well draining with a pH of around 6.5 to 6.8.