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- A good weed control program must be put in place two to three years prior to establishing alfalfa. Pay attention to the herbicide's re-cropping restrictions, since herbicide residue can affect seedling survival rate.
- Ensure that the field has been rotated out of alfalfa long enough to break the disease cycle. One year will meet the requirements for autotoxicity, but is not long enough for reducing the disease load. Two to three years are required to reduce the inoculums that cause crown and root rots. This is equally, or more, important than autotoxicity.
- Select a well-drained soil with a moist seedbed in the spring.
- Fertilize according to a soil test. A soil analysis should be done a year before establishment.
- A pH of 6.5 –7.0 is best for alfalfa.
- A small application of 20 to 40 lbs of nitrogen per acre when seeding can improve yields. More than 40 lbs/acre will reduce the formation of nodules and future nitrogen fixation.
- Ensuring adequate soil phosphorus prior to seeding will increase seedling root growth. Phosphorous is more effective when it is banded or incorporated into the soil than when broadcast.
- Yield and stand survival rate are highly dependent on adequate potassium levels.
- Sulphur may be required as indicated by a soil test. Sulphur should be incorporated before seeding because, like phosphorus, it is not very mobile in the soil.
- Select a variety with good yield potential, pest resistance and winter hardiness.
- Use seed with a high germination rate and that is accompanied by a seed test certificate indicating cleanliness from weed seeds.
- Inoculate seed with live rhizobium bacteria specific to alfalfa to create nitrogen fixing nodules.
- Good seedbed preparation is very important. When walking across the field, your foot should not sink more than 3/8 of an inch. Do not over pack heavy soils since they are prone to crusting, leave them lumpier and increase the seeding rate.
- Seed in firm seedbed ¼ to ½“ deep to a maximum depth of ¾” in sandy soils. Seed 10 lbs per acre to achieve approximately 25 to 30 plants per square foot.
- Seed at the appropriate time. Spring is the best, fall is riskier especially if seed germinates, resulting in winter kill.
- Cover crops can be used to establish alfalfa, but reduce forage yield and compromise plant vigor if stressed. If using a cover crop, seed the cover crop at half the normal seeding rate to reduce competition. Harvest the cover crop early as greenfeed or silage to allow the seedlings time to establish.
- Grass species that grow well when planted with alfalfa include: meadow bromegrass, hybrid bromegrass, timothy, crested wheatgrass, orchard grass, smooth bromegrass and tall fescue. Choose a grass species that is not competitive.
Alfalfa Germination and Growth - requires purchase
Alfalfa: Seed Germination, Seedling Growth and Vegetative Development
Alfalfa Stand Assessment
Alfalfa Stand Renovation: Reseed or Crop Rotation - available in PDF format only
Coated Alfalfa Seed, is it worth it?
Establishing Alfalfa the No-Till Way - available in PDF format only
Improving Survival of Sod-Seeded Alfalfa
Replant Decision-Making for Alfalfa
Round Up Ready Alfalfa: An Emerging Technology
Seeding and Renovating Alfalfa
Selecting Alfalfa Varieties for Manitoba
Sod Seeding Alfalfa
Ascophyllum nodosum Extract and Its Organic Fractions Stimulate Rhizobium Root Nodulation and Growth of Medicago sativa (Alfalfa) - available only as abstract
Seedbed preparation, timing of seeding, fertility and root pathogens affect establishment and yield of alfalfa - available in PDF format only