Alfalfa is a popular legume that can be grazed or fed as hay to cattle and horses. With the proper management, harvested alfalfa can last five years or more. Alfalfa seeds are available at farm and feed supply stores. The most recommended seed types have a high yield percentage, can handle winters, and can fight off anthracnose, bacterial wilt, and root rot.
Choose a planting location with well-draining soil. Alfalfa grass will not grow well in spots with pooling water.
Collect soil samples and have them tested six months to a year in advance. University cooperative extensions do testing, and there are test kits available at nurseries. Alfalfa thrives in a soil pH of 6.0 to 6.5, and the plant needs the right mixture of fertilizer and agricultural lime to grow successfully. If lime is needed, it should be added to the soil six months to a year before you plant alfalfa.
Spread starter fertilizer that matches the results of the soil test. Typically, alfalfa prefers a fertilizer with more phosphorus than nitrogen or potassium. Phosphorus encourages root growth for winter survival, resistance to summer drought, and fast growth in the spring. Choose a fertilizer with a higher middle number such as 20-60-20, because this indicates more phosphorus. Follow the soil test recommendations for exact amounts. Work the fertilizer into the soil well to keep it from contacting germinating seed.
Remove weeds and debris. Alfalfa grass seed needs direct contact with the soil to germinate and develop a root system.
Loosen the soil with a rototiller. Alfalfa grass has a shallow root system and grows easily. It can be broadcast or drilled into a prepared seedbed.
Disperse seed over the prepared bed in the early spring. If you live north of the Missouri River, an alternate planting time is late summer. According to the University of Missouri Extension, broadcast 15 pounds of seed per acre if you're planting alfalfa alone, or 10 pounds per acre if you're also planting grass seed. Rake the seed gently into the soil to cover it with 1/4 inch. This will hold it in place. The Samuel Roberts Noble Foundation recommends alfalfa seeds be drilled into the field.
Water until the soil is moist. Check it once a week, and add water whenever the soil is dry. Do not make the ground wet, or the seed may rot.
Test another soil sample after two years of alfalfa growth. The results will tell you if additional fertilizer or limestone is needed.