There are no broadleaf herbicides registered for buckwheat. Some broadleaf herbicides used in previous crops may present residual problems in buckwheat. Canada thistle, sow thistle, toadflax and quack grass should be sprayed with pre-harvest glyphosate the year prior to growing buckwheat. Cultural control is often used to achieve weed control. Since buckwheat is planted somewhat later in the season, a number of tillage operations are possible prior to seeding.
Diseases There are few reports of diseases in buckwheat.
Leaf spot caused by a fungus called Ramilaria can occur. None of these diseases is of any economic importance. Insects Japanese beetles, aphids, cutworms and wireworms have all been reported in buckwheat. Japanese beetles do the most damage, attacking the flower head and can cause major economic loss on occasion. Marketing The Japanese market requires new crop buckwheat for Soba noodles.