By Emma Matcham and Kyle Verhoff et.al
Frost seeding is a relatively inexpensive practice that can introduce more legumes, and thus more nitrogen fixation, into many pastures. Below are some answers to frequent questions related to frost seeding.
When should I frost seed?
February is the optimal time for frost seeding in most of Ohio. The goal is to distribute seed while there are a series of freeze-thaw cycles, since that is what increases seed-soil contact for emergence.
Which species and varieties are good for frost seeding?
Clovers are the most common species for frost seeding, and most frost seeding research to establish seeding rate and timing recommendations was performed using clover species. Birdsfoot trefoil is another legume option, and annual ryegrass, orchardgrass, and some other grasses can also be established this way. But, plant establishment from frost seeding is usually higher for clovers than other species.
Can I frost seed multiple species at the same time?
Yes, but be careful to adjust seeding rates proportionally based on your desired species mix.
Source : osu.edu