Alfalfa is the most important legume for hay and pasture in Manitoba. Its high protein content makes it an important source of livestock feed. And since alfalfa is a nitrogen fixing legume, proper inoculation eliminates the need for nitrogen fertilizer.

When growing alfalfa for hay, pasture or seed, there are certain guidelines which should always be followed:

• sow in a firm, well prepared seedbed

• use pedigreed seed of recommended varieties

• inoculate with the proper nitrogen fixing bacteria

• follow soil test recommendations for fertilizer application

• implement an effective weed control program A major consideration is the selection of the variety to be grown. It is important to use varieties that will produce high yields of quality forage and persist in our climate. In Manitoba, varieties are recommended because of their performance under Manitoba conditions. Varieties not recommended have either not been tested in Manitoba or are considered inferior, so there is an element of risk in growing such varieties.

• Choosing The Correct Variety
• Winterhardiness and Bacterial Wilt Resistance
• Two Types Available
• Hay and Pasture
• Three Categories of Alfalfa
• Soil Conditions 
• Summary

Winterhardiness and Bacterial Wilt Resistance

The adaption of an alfalfa variety in Manitoba is largely dependent on winter climate. The terms very hardy, hardy, and moderately hardy describe the variety's ability to survive and produce in areas that have severe or medium winter climates.

As the degree of winterhardiness increases, so does the plant's ability to become dormant in the fall. Generally, the most persistent winterhardy varieties initiate growth slowly in the spring, recover slowly after cutting and become dormant (inactive) relatively early in the fall. Less winterhardy varieties begin growth early in the spring, regrow rapidly after clipping and continue to grow late in the fall. They are, therefore, less likely to persist for more than two or three years.

Bacterial wilt resistance is another important factor in the longevity and adaptation of a stand. Bacterial wilt is closely related to winter injury. Winter injured stands are susceptible to attack by bacterial wilt and diseased stands are weakened and easily winterkilled.

If stands are to survive in Manitoba, the alfalfa variety grown must have a high level of winterhardiness and bacterial wilt resistance.

Verticillium wilt is a potentially destructive disease prevalent in some areas of Canada. The disease has been identified in eastern parts of the province in low quantities.Many new varieties on the market are resistant to verticillium wilt.

Two Types Available

The alfalfa varieties grown in Manitoba fall into two categories - Variegated or Flemish.

Variegated alfalfas (Medicago media) are derived from crosses between M. sativa (purple flowered) and M. falcata (yellow flowered) alfalfa. Their flowers range in color and can be purple, blue, yellow or white. The most cold-tolerant varieties grown in Manitoba are variegated. These have been bred to combine winterhardiness and drought tolerance with good yield and satisfactory regrowth.

Flemish type alfalfa (M. sativa) originated in northern France. They have purple flowers and are early growing, quick to recover after cutting and moderately winterhardy. Flemish alfalfas usually mature two to five days earlier than Vernal (a variegated type) and should be harvested several days earlier than variegated types to maintain quality.

• rapid spring growth
• may provide more & earlier regrowth than medium maturing varieties

• least winter hardy

• more winter hardy than early maturing varieties
• persistent on marginal soils

• 2-5 days later in maturing than early varieties

• more flood and drought resistant than other categories
• withstands grazing pressure better
• persistent on marginal soils
• most winter hardy

• lower yields than other category

Note: With all alfalfa varieties the possibility of pasture bloat should be considered when grazing livestock.