How to Sow Buckwheat
Seedbed preparation
Since the buckwheat plant has a fine root system, preparing a good seedbed is time well invested. The seedbed should be firm to obtain uniform establishment, rapid plant growth, uptake of essential nutrients, to reduce drought injury, and to lessen lodging. Avoid sowing in wet soil because it usually turns out very hard before the root has a chance to grow.
Since buckwheat is planted late, it is often valuable to plow and disk in early to mid-June in order to retain soil moisture.
When buckwheat is sown in abandoned fields, old pastures, or other land that has not been cultivated for several years, it is best to allow the vegetation to break down by plowing deeply several weeks before sowing. The soil should then be harrowed periodically to improve its physical condition, retain moisture, and destroy weeds.
If the field was in small grain or a cultivated crop (such as potatoes) the previous year, or if the soil has already been prepared for another crop, plowing can be replaced by disking or harrowing with a spring-tooth field cultivator or vibrashank. Plowing is usually necessary in all other situations.
Unfortunately, many first-time buckwheat growers assume that buckwheat planting requires little attention. When they plant by doing a rough disking, broadcasting seed, and disking again, they are always disappointed. Seeding is the last operation before harvest - it is worth doing right.
Sowing
Buckwheat should be sown with a grain drill at a depth of 1/2 to 1 inch. Seeding deeper than 1 1/2 inches will usually lead to poor and uneven stands. Drilling the seed will produce an even and uniform stand. If a drill is not available, a crop can be obtained by broadcasting the seed at double the usual seeding rate, followed by cultipacking.
The seed should be sown at 40-55 lb/ac. Larger plants will grow on good land, so the lower rate can be used. Higher rates are needed if plant growth is likely to be slow (e.g. if the soil is cold, wet, or poorly prepared at sowing). Large-seeded varieties require slightly higher rates than "common" seed because there are fewer seeds per pound. These seeding rates are based on 85% germination. Germination can decline quickly in common storage, so a germination test is worthwhile if the seed is not from the most recent harvest.