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Department of Agronomy

Kansas State University

1712 Claflin Rd.

2004 Throckmorton PSC

Manhatan, KS 66506

785-532-6101

agronomy@ksu.edu

Extension Agronomy

Fall planting of alfalfa

Late summer and early fall are often the best times to plant alfalfa in Kansas. With the June rains in most areas of Kansas, there may be enough moisture to achieve good stand establishment in at least some fields. A fall-seeded crop is more productive during the first growing season than a spring-seeded crop. After the first season, however, yield potential is about the same.

Growers in northwest Kansas can plant as early as Aug. 10-15. Those in southeast Kansas can plant in mid- to late September. In other parts of Kansas, planting time is late August or early September.

Producers just need to plant early enough to have three to five trifoliate leaves before the first frost. Alfalfa is a three- to five-year or longer investment. Some producers shy away from alfalfa because of its high establishment cost and risk of stand failure. In the long run, however, it’s relatively inexpensive, if amortized over the life of the crop.

If managed properly and if we have a good year in terms of weather, dryland alfalfa can produce four to six tons of forage per acre per year. Irrigated fields can produce 8 to 12 tons per acre per year.

When planting alfalfa, producers should keep the following in mind:

Test the soil. Alfalfa grows best in well-drained soils with a pH of 6.5 to 7.5. If the land needs lime, add it before planting. Apply the needed phosphorus and potassium, too. Phosphorus is an annual input.

Plant certified, inoculated seed. Inoculation helps alfalfa seedlings fix available soil nitrogen for optimum production.

Plant in firm, moist soil. A firm seedbed ensures good seed-soil contact; therefore, use a press wheel with the drill to firm the soil over the planted seed. No-till planting in small-grains stubble will usually provide a good seedbed.

Don’t plant too deeply. Plant one-fourth to one-half-inch deep on medium- and fine-textured soils and three-fourths-inch deep on sandy soils. Don’t plant deeper than 10 times the seed diameter.

Use the right seeding rate. Plant 8 to12 pounds of seed per acre of dryland in western Kansas, 12 to15 pounds per acre in irrigated medium- to fine-textured soils, 15 to 20 pounds per acre on irrigated sandy soils, and 12 to 15 pounds per acre of dryland in central and eastern Kansas.

Check for herbicide carryover that could damage the new alfalfa crop – especially when planting alfalfa no-till into corn or grain sorghum stubble. In areas where row crops were drought-stressed and removed for silage, that set up a great seedbed for alfalfa, but may still bring a risk of herbicide damage.

Choose pest-resistant varieties. Resistance to phytophthora root rot, bacterial wilt, fusarium wilt, verticillium wilt, anthracnose, the pea aphid, and the spotted alfalfa aphid is essential. Some varieties are resistant to even more diseases and insects.

More information about growing alfalfa in Kansas can be found in the Alfalfa Production Handbook. That information also is available on the web at: www.ksre.ksu.edu/bookstore/pubs/c683.pdf

 

Jim Shroyer, Crop Production Specialist Emeritus
jshroyer@ksu.edu