Fall-seeded alfalfa usually produces more first-year tonnage, but stand-establishment failures are less likely with spring seedings because moisture conditions typically are more reliable, says Jim Shroyer, Kansas State University Extension agronomist.
Before planting, he says to have the soil tested for pH, phosphorus and potassium. There’s still time to get that done before a spring seeding, and the results will pay off for the life of the stand, says Shroyer.
“Past research in Kansas has shown that applying and incorporating phosphate fertilizer, if recommended by a soil test analysis, results in large increases in productivity,” he says. “In a no-till situation, phosphate fertilizer can be surface-applied and still have a long-term beneficial effect on yields.”
Lime may be needed before planting as well, Shroyer adds.
“Alfalfa does best when the soil pH ranges from 6.5 to 7.5. If the soil pH is less than 6.5, production will be reduced. At very low pH levels, the stand may be thin and weedy. Applying lime, if needed, before planting alfalfa will pay big dividends.”
Growers should make sure no weeds are growing when the crop is planted and there’s no herbicide carryover that could injure the seedling alfalfa. Seeding at the proper depth can help achieve good stands.
“When seeding alfalfa, plant seed ¼-½” deep. Plant about ¾” deep in sandy soils, unless the field is irrigated. For dryland production, use a seeding rate of 8-12 lbs per acre in western Kansas; 12-16” lbs per acre in central and eastern Kansas. For irrigation production, use 15-20 lbs of seed per acre in all soils.”
It’s also important to use certified, treated and inoculated seed, Shroyer advises.