Frost-seeding is one method to achieve overseeding. This is a great way to add legumes to thicken or repair an existing pasture or hay field during the winter months. If timed and managed properly, frost-seeding has great odds of success. Clover contributes to higher yields of grasses by fixing nitrogen at a lower cost than fertilizer. Legumes can help offset the summer slump that grasses experience as well as increase nutritional value of the forage. Red clover has the potential to increase forage yields by 30% and as well as giving a slight boost to the forage protein levels approximately by 3.5%. Red clover is more agronomically adaptable and more palatable as a forage than alfalfa.
When is frost-seeding right for my farm?
Frost seeding should be performed if you fit the following criteria.
A pasture or hayfield is thinning, and more legumes are needed in the stand, there is exposed soils, and the existing stand is grazed or mowed down short from the fall. Or, a field with a fall-planted small grain (grown for a grain, not forage), in which a legume, cover crop and or a hay crop is to follow the grain crop. This is a relatively new concept.
A Guide for Best Success:
Open Soil- Make sure there is little competition from the existing stand and plenty of exposed soil, (free of residues and existing stand). In a pasture or hayfield situation and if not much bare ground is exposed you can try to lightly vertically till, chain drag, or disk.
Ideal Weather Conditions- The ground should be frozen in the morning, this way you are able to drive or walk across the soil surfaces to broadcast without compacting soils. The ground should thaw by afternoon. The freeze-thaw cycle causes the expansion and contraction of the soil creating a honey-combing effect, which works the seed into the soil. Ideally, having several weeks of fluctuating temperatures is optimal for achieving best seed to soil contact. You will see better expansion and contraction in soil that is clay based versus sand based since clay holds more water content. In addition to the freeze-thaw cycle, you can also use livestock to tramp the seed into the soils.
Soil Conditions- Be sure that the soil conditions are hospitable to new seedlings. Components to verify would be drainage, pH, and nutrient content. Pastures with high nitrogen levels are not as ideal as the grasses will take off very rapidly in the spring, creating lots of competition to the new seedlings. Because of this, the clovers in the stand may not be seen until the summer months.
Appropriate Species- It is important to use species that are proven to perform by the frost-seeding method. Red clovers work great due to the small round seed size, along with the vigorous seedlings that are shade tolerant, allowing the seedlings to thrive under the canopy of the existing stand. Red clovers tolerate a broad range of conditions such as pH, fertility, drainage, and drought. White clover is a great option as well. However, red clover is ideal for grazing or haylage only systems as it provides better yields. A mix of red and white clovers works great in a pasture or small grain setting and establishes greater diversity.
Freedom Red!, and Common Medium Red Clover, Dutch White, Alice, and Premium Clover Blend.
Alfalfas and grasses can be frost seeded. However, they are not as successful due to their larger seed size and shape. As a result, the seeds do not work their way down into the soil surface. If you decide to frost-seed grasses with other species be wary that the seed will broadcast at a different rate due to varying size/shape. If you decide to frost seed alfalfa, do not seed it into existing alfalfa as it is autotoxic. Grasses that have occasionally worked for frost seeding are the small seeded ryegrass, or hulled orchard grass. Some clover species are not recommended for pastures during this early-season timeframe.
Not Recommended Clovers:
Mammoth Red Clover, Crimson Clover
Inoculant- Legumes need inoculant at the time of planting to ensure optimal nitrogen fixation. Many of our clovers come with a coating that includes inoculant.
Suggested Seeding Rates- Red clovers should be spun on at 3-4lbs per acre if frost-seeded every year, or 6-8lbs per acre if every other year or first time seeding. White clovers should be spun on at 1-2lbs per acre since they are long lasting and do not need to be seeded annually.
Management- After frost-seeding, treat the new seeding as you would any new stand. The clovers will not yield much until early summer, after the first cutting and after the stand is opened up.
Speak to an expert at King’s AgriSeeds now at 1-717-687-6224 or email us at [email protected].