Common buckwheat (Fagopyrum esculentum) is thought to have originated in central and western China from a wild Asian species Fagropyrum cymosum. It has been cultivated in China for over 1,000 years, and was brought to Europe during the Middle Ages. Buckwheat, as well as other grain species, accompanied the colonists to the New World.
The Scots coined the word “buckwheat” from two AngloSaxon terms, boc(beech) and whoet(wheat). The word beech was used since the fruit of the plant was similar to that of beechnut. It was called wheat because the grain of buckwheat was used in the same way as wheat. This term is somewhat ironic since buckwheat does not belong to the grass family and is not considered a “true” cereal.
World acreage of buckwheat has been as high as 5 million acres (2 million hectares). Producers include the former Soviet Union, China, Brazil, Poland, France, Japan, United States, South Africa and Australia. The former Soviet Union (54 per cent) and China (38 per cent) make up the largest percentage of world production.
In Canada, buckwheat production was approximately 150,000 acres (60,700 hectares) in the late 1970’s and early 1980’s, but has since declined to 30,000 to 40,000 acres (12,000 - 16,000 hectares) annually.
Manitoba is the major producer of buckwheat in Canada with 70 per cent of the acreage on average, followed by Quebec at 16 per cent and Ontario at 14 per cent. In Alberta, the annual acreage has been 500 acres (200 hectares) for a number of years. The Canadian 1993-95 yield average was approximately 21 bushels per acre; however, the long-term information from 1981-91 shows average yields closer to 16 bushels per acre.
Description
Buckwheat is an annual, characterised by large heartshaped leaves. The tall, erect plant can grow from 2 to 5 ft. (.6 - 1.5 m) in height and can produce several branches . Stems are hollow and the plant is very prone to lodging. Stems vary in colour from green to red and brown at maturity. Buckwheat has a shallow tap root system, with numerous laterals extending to 3 to 4 ft. (9 - 1.2 m) in depth.
The fruiting structure of buckwheat is on axillary or terminal racemes with densely clustered flowers . Flowers can be white or white tinged with pink. Seeds are wide at the base and triangular to almost round in cross section. Seed colour may be brown, greybrown or black while size varies according to variety. The seed is comprised of a thick outer hull and an inner groat.
Buckwheat has an indeterminate growth habit, so the crop does not mature uniformly. Plants will begin to blossom 5 to 6 weeks after sowing and will mature in 80 to 90 days. Buckwheat requires cross pollination to produce seed, so insect pollinators are essential for effective fertilization and seed set. Manitoba research recommends one honey bee colony per acre.
Adaptation
Buckwheat thrives in cool, moist climates. It is not frost tolerant. Because of its short growing period, buckwheat is well adapted to Canadian conditions. High temperatures and dry conditions during flowering may cause some flower blast and lower yields. Cool evening temperatures and high humidity favour buckwheat growth.
Buckwheat can be grown on a wide range of soil types, but it is best suited to light and medium-textured soils, such as sandy loam, loam and silt loam. Clay soils and highly fertile soils should be avoided. Buckwheat is as acid tolerant as oat or potato. Liming soils above a pH of five should not be necessary. Studies in western Canada have shown an early growth-stage tolerance to saline soils; however, as the crop matured, this tolerance lessened.
Growers in areas with frequent heavy rain and strong wind should consider the risks in growing buckwheat. It is very susceptible to lodging because of its hollow stem and is easily flattened by high wind and heavy rain.
Properties and uses
In Canada, buckwheat has been grown primarily for grain for domestic and export purposes. Throughout history, this crop has had a number of uses: food for humans, feed for livestock, a honey crop, smother and green manure crop.
Buckwheat is also harvested green for rutin extraction. Rutin, a flavonol glycoside compound, is used in medicine to check blood vessels for haemorrhagic diseases and to treat high blood pressure. The leaves of buckwheat contain the highest level of rutin.
Canadian processors use buckwheat in pancake mixes, breakfast cereals, breads and poultry stuffing. Europeans use whole groats in porridges, soups and breakfast cereals. Japan is the largest customer for Canadian buckwheat. Processors in Japan grind buckwheat into flour and combine it with wheat flour to produce “Soba” or buckwheat noodles. The term “Soba” is simply the word for buckwheat. Japanese consumers are very particular about the quality of Soba noodles, and only new crop buckwheat has the desired colour and flavour.
Buckwheat grain is of lower quality than cereal grains when used for livestock feeds and is usually fed in combination with barley, oats or corn. Whole grain protein is approximately 11 per cent, with 2.5 per cent fat. Buckwheat contains over 1 per cent of three amino acids: glutamic acid, arginine and aspartic acid.
The middlings from buckwheat grain are rich in protein, fat and minerals. Generally, middlings are fed only as a concentrate. The protein content of middlings is approximately 27 per cent and fat 7 per cent. The palatability of this product is poor, and it is not fed to swine.
Buckwheat produces a dark, strong-flavoured honey, which is usually sold for a premium. One acre (.41 ha) of buckwheat may produce up to 150 lb. (65 kg) of honey per growing season.
Buckwheat has also been used as a smother crop for controlling weeds such as quack grass, Canada thistle, sow thistle, leafy spurge and Russian knapweed. The crop’s rapid germination and growth and broad-shaped leaves, which shade early in the crop’s development, smother most weeds. Buckwheat is not a good choice for a cover or companion crop. It has also been used as a green manure crop because of decent yields of dry matter in a short time.
