Tips for planting alfalfa
Long -term alfalfa productivity depends on successful stand establishment and maintenance. Achieving a profitable stand of alfalfa is the result of proper field selection and utilizing proven production practices to ensure germination and establishment.
Alfalfa requires a well-drained soil for optimum production. Poor soil drainage can cause problems with soil crusting which may cause poor soil aeration, micronutrient toxicity, and ice damage during winter.
It is important to remember to take soil samples before planting to determine the pH and nutrient status of the field. There are 18 nutrients (macronutrients and micronutrients) essential for alfalfa growth. Some of the most important macronutrients include phosphorus and potassium. Phosphorus helps root growth and seeding success. Each ton of alfalfa removes 12 lbs of phosphorus. To maintain soil test levels, a common practice is to apply 2 years of crop removal every other year. In the year of establishment, the amount applied can be adjusted according to soil test level. Many Western South Dakota soils contain very high levels of potassium. Potassium has little effect or influence on improving stand establishment, but if soil test levels indicate need, enough potassium should be added to meet the needs of the alfalfa and/or companion crop.
Alfalfa requires a firm seedbed to ensure good germination. Firm seedbeds will reduce the possibility of planting too deep and help hold moisture closer to the surface. Packing the soil will help to insure a firm seedbed and good soil moisture retention. No-till can provide a firm seedbed and weed control. Delaying planting to allow time for weeds to emerge for a burndown application may be advantageous.
For best results in South Dakota alfalfa should be typically seeded between mid-April to mid-May. The second choice is late summer (Aug. 1 to Sept. 1) if soil moisture is adequate, at least eight weeks before a hard frost. The third choice is dormant planting, usually after mid-November.
Alfalfa seed should be covered with enough soil to provide moist conditions for germination. Seed placement of 1/4 to 1/2 inch deep is appropriate on most soils at rates from 10 to 25 lbs per acre. Be sure to inoculate alfalfa seed with nitrogen-fixing bacteria before planting.
Seeding alfalfa with a spring small grain companion crop can help to minimize weed competition during establishment, reduce emergence problems from crusting, and reduce soil erosion when planting into black ground. Planting alfalfa without a companion crop will produce more alfalfa with higher quality in the seeding year. Some producers will plant the alfalfa with a companion crop and kill it with a post-emergent herbicide at an early growth stage.
Pure stands of alfalfa will produce the highest quality forage and have the highest demand from the dairy industry. Beef and sheep producers may be interested in using alfalfa/grass blends for improved persistency and yield while still producing quality forage. Alfalfa-grass mixtures also offer the advantages of reduced weed pressure and soil erosion and fewer problems with alfalfa weevils.
For more information, visit http://igrow.org/agronomy/other-crops/.