By Blake Jackson
Frost seeding offers a cost-effective method to establish cover crops or improve existing forage stands within winter wheat, barley, or pastures. While not guaranteed, it yields decent success rates.
The ideal time for frost seeding is during February and March when freeze-thaw cycles occur. This natural process creates a "honeycombing" effect in the soil, enhancing seed-to-soil contact for better germination.
Loamy and clay soils that retain moisture are most suitable for this technique. Sandy or shaley soils, prone to drying quickly, are not ideal.
Early mornings, when the ground is frozen with a thaw expected later, present the perfect window for frost seeding. This minimizes soil compaction while promoting the desired soil movement for optimal seed contact.
Species with small seeds that germinate quickly and thrive in cool conditions are best suited for frost seeding. Red, white, and sweet clover are prime choices. Birdsfoot trefoil, though slower to germinate and establish, can also be used for pasture renovation.
While yellow sweet clover contains coumarin, a blood thinner posing potential health risks for animals, its presence in small quantities within a pasture is unlikely to cause problems.
Legumes require inoculation with appropriate rhizobium bacteria before broadcasting to establish the nitrogen-fixing symbiosis. In pastures, some non-fluffy grasses like annual or perennial ryegrass can also be frost seeded.
Avoid mixing grass and legume seeds for broadcasting, as legumes' higher density leads to uneven distribution. Aim for uniform coverage by calculating the spread width and spacing between passes.
Seeding rates vary depending on the crop and location. Consult the article for specific recommendations for red clover, yellow blossom sweet clover, white and ladino clover, birdsfoot trefoil, and annual/perennial ryegrass.
Higher seeding rates are recommended for small grains, as these applications cannot be repeated. Pasture renovation allows for reseeding the following year if needed and utilizes heavier rates in thinner areas.
Mixing clovers for pasture renovation is a common practice. Red and ladino white clover offer a good combination, with a 2:1 seeding ratio (2 lbs red to 1 lb white, up to 6 lbs red and 3 lbs white).
Frost seeding success in pastures is heightened with bare spots or overgrazing. Additionally, controlled grazing shortly after broadcasting can improve seed-to-soil contact, particularly in pastures with thick thatch. However, avoid grazing in wet conditions to prevent soil compaction.
While the ideal window might be missing, clover seeds can remain viable in the soil and germinate when conditions become favorable. If your stand remains inadequate in summer, consider selective no-till seeding of legumes and/or grasses to address any remaining issues.
Photo Credit: gettyimages-mvburling
Categories: New York, Crops