Beta vulgaris Seeds | Sugar Beet
LATIN NAME: Beta vulgaris
COMMON NAME: Sugar Beet
Plant Profile
Sugar beet is a biennial of the amaranth family, grown as an annual crop for the swollen root that stores sucrose through the first season. The root is white, conical and can weigh a kilogram; the leaves form a rosette above it, and in the second year the plant would send up a stem of green flowers.
The crop supplies about a fifth of the world’s sugar, most of it in temperate countries where cane will not grow. A good field yields sixty to seventy tonnes per hectare at sixteen to twenty per cent sucrose. The crop is grown from seed each year, and no part of the plant is left in the field after harvest except the tops.
Science & Biotechnology
Breeding has solved two problems that once made the crop unworkable. The seed is naturally a glomerule, a corky ball containing two to five seeds, which made singling the seedlings by hand necessary; monogerm lines, bred from a single-gene recessive, now allow precision drilling.
The second is bolting. Sugar beet needs vernalisation to flower, and cold spring weather can push young plants into stem growth, which ruins the root. Modern varieties are selected for bolting resistance, and the crop is sown once soil reaches 6°C. Cytoplasmic male sterility and triploid hybrids are used to combine vigour with uniformity. Sugar content is measured at the factory gate with a refractometer, and growers are paid on that reading rather than on tonnage alone.
Uses & Benefits
The root is sliced into cossettes and diffused in hot water, and the juice is purified with lime, concentrated and crystallised. Molasses, pulp and lime cake are by-products used as feed and fertiliser.
In the garden, beetroot for the table is the same species, selected for colour and flavour rather than sugar. Sugar beet itself is edible but coarse and low in the pigments that make garden beet attractive. The pulp left after diffusion is pressed and dried into pellets, which are fed to dairy cattle through winter. Beet molasses is darker and more bitter than cane molasses, and most of it goes to fermentation and to animal feed rather than to the table.
Growing from Seed
Sow direct, one centimetre deep, when the soil has warmed, and thin to twenty centimetres. The seed ball gives a cluster of seedlings, so thinning is essential with older varieties.
The crop wants deep, stone-free soil, a neutral pH and steady moisture; Boron deficiency causes heart rot and is corrected with a foliar spray. Rhizomania, a virus transmitted by soil-borne protozoa, is the main disease threat, and resistant varieties are the practical answer. Harvest at five to six months, before hard frost. A fine seedbed matters, because the seed ball is small and germinates best in firm, moist ground.
Our Take
A crop that looks like a root and behaves like an industrial process, and one of the clearest examples of how plant breeding reshaped a whole food supply.
Related Reading
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