It's Frost Seeding Time

March 3, 2022 8:54 AM
Blog Post

Frost seeding is the easiest and least expensive method for adding new legumes to a pasture. And now is the perfect time to be doing frost seeding.

The goal of frost seeding is to seed while the soil is frozen (usually first then in the morning) and get the seed in contact with bare soil (not on top of snow) and to then use the freeze-thaw cycles to help provide the seed-to-soil contact. If we happen to get a snow that accumulates after we’ve frosted seeded on bare ground, that is fine. Additionally, it is recommended that frost seeding be targeted on areas that are the thinnest or maybe have bare soil exposed due to heavy grazing or disturbance.

Red clover has been the Iowa forage species of choice for frost seeding because of its quick establishment, small seed size and ability to grow in a variety of soil and environmental conditions. Other legumes, such as white clover, alsike clover, and birdsfoot trefoil, also can be frost seeded but with less success than red clover. It is not recommended to frost seed alfalfa. In general, frost seeding does not work as well with many types of grasses, primarily due to the larger seed size not working through the soil surface as easily.

Below are suggested seeding rates for frost seeding by species.


Seeding Rate (lbs/acre)

Red Clover

4 to 10

Alsike Clover

1 to 4

Ladino Clover

1 to 3

Birdsfoot Trefoil

5 to 8

Annual and Korean lespedeza

8 to 15

A few well-researched steps will improve the success of frost seeding. Those steps, seeding rates and guidelines are available in the ISU Extension and Outreach publication Improving Pasture by Frost Seeding.


Aaron Saeugling Field Agronomist in SW Iowa

Aaron Saeugling is a field agronomist in southwest Iowa for Iowa State University Extension and Outreach.


Rebecca Vittetoe Field Agronomist in EC Iowa

Rebecca Vittetoe is an extension field agronomist in east central Iowa. Educational programs are available for farmers, agribusiness, pesticide applicators, and certified crop advisors.

Areas of expertise include agronomy, field crop production and management of corn, soybeans, and...