If you’re lucky enough to have completed harvest before snow fell on your fields — but haven’t planted a cover crop yet — not to worry. Planning ahead for a late winter or early spring frost seeding of covers might still be a viable alternative.
A benefit of frost seeding is that you can still get an increase in weed seed predation by creating habitat for biocontrol agents such as rodents and insects. Plants can still get more nitrogen (N) through N fixation, and forage protein levels get a boost, too, which is critical if the covers will be grazed.
The key to frost seeding is all in the timing. The snow has to be melted so you can get your seeding equipment into the field, and then the freeze-thaw action of the soil does the hard part, working the seed into the soil.
Frost seeding should be done early enough in the season to allow for several freeze-thaw cycles. USDA NRCS recommends frost seeding early in the morning, when frost is still in the soil.
Experts from Michigan State University Extension say frost seeding can be a simple and inexpensive way to establish a cover or improve a forage stand with minimal soil disturbance.
Another major factor in the success of frost seeding is the type of cover planted. Only the hardiest plant species with thick seed coats can survive — such as legumes (clover, alfalfa and trefoil), and brassicas like mustard and rapeseed are also good choices.
Red clover is also a popular selection. Frosty berseem clover is the first cold tolerant berseem clover, according to Grassland Oregon, and is excellent for livestock producers because it does not cause bloat in cattle.
One word of caution with frost seeding: If fall weed management practices are unsuccessful, frost-seeded covers will probably not be able to compete with established weeds, Michigan State University Extension experts say.
Have you had success with frost seeding? Let us know in the comments section below this article.