Frost Seeding Frost seeding is an economical method of improving pasture and hay fields by spreading the seed on frozen ground. As the ground freezes and thaws, it opens and closes allowing the seed to be incorporated into the soil. This keeps the seed from germinating until there is a good moisture supply early in the spring. Legumes are the most successful for this system as they tend to be rounded and dense. Grasses have not been as successful as they are lighter coloured, less dense thus they sit on top of the ground and wait for warmer temperatures to begin growth. The ideal candidate for frost seeding is a pasture field that is "run out". If you walk across the field and can see bare soil the size of a loonie, then these spots will be good frost seeding sites. A field can be made ready for frost seeding by overgrazing in the fall to weaken the existing plant growth in the spring. This is not necessary but can be helpful in allowing the seeds to make good soil contact. You have the choices of conventional reseeding no-tilling, fertilizing or frost seeding forage fields to improve their production. Your goals for the field and the condition of the field will determine which is best for you. In hay fields, we generally want an alfalfa grass stand so conventional reseeding or no-tilling, after killing the original stand, are the most effective. Alfalfa stands can be patched by frost seeding red clover into the stand to get one more production year, but this is usually done in the spring when winterkill reduces hay supplies. Fertilizing, can double or triple the production from an existing stand, but keep in mind that it could also do this with a more productive species that you have introduced. If you have an adequate grass stand in a pasture field, then adding a legume by frost seeding will not only add a high quality plant to the stand but will also help to provide nitrogen to the grasses, improving their growth as well. Frost seeding requires very little equipment. It is often done using an all terrain vehicle, snowmobile, tractor and spreader or with a hand-held broadcaster. Cost per acre is low. This makes it a very attractive alternative for someone who wants to improve a pasture with very low input costs. It also has the added advantage that the pasture will be useable the summer following as there is no need to remove the livestock completely. The ideal time to frost seed is in the very early spring. The ground should freeze and thaw 2 - 3 times after the seed is broadcast. Another good time is December, after all the growth has stopped for the year. This is an excellent time for the Atlantic Provinces which normally receives good snow cover and without a prolonged January thaw. Frost seeding is a popular method of improving long term pastures or patching hayfields for one more year of production. It is a cheap but high risk option. Many people will frost seed 25% of their acreage each year so that they are spreading their risk over different years. It takes about two years to see the improvements from trefoil applications so these should be made a year before the existing plants die out. This will continuously maintain a good pasture rather than allowing it to lower its production. Frost seeding is one of the most economical and easy improvements that can be made to a pasture. Source: Ontario Ministry of Agriculture