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 not 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 when the soil has already been prepared for another crop, plowing could be replaced with disking or harrowing with a spring-tooth field cultivator or vibrashank. Plowing is usually necessary in all other situations.
Unfortunately, many first-time buckwheat farmers 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.
The seed should be sown at 40 to 55 lb per acre. 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, for example 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.