Beet (Beta vulgaris, L. 1753)

Identity

Beet (Beta vulgaris L., 1753) is a vegetable in the genus Beta, in the Amaranthaceae family. This biennial species is almost always grown as an annual: its root or leaves are harvested during the first year, before it flowers. ^{1 3}

Several very different crops share this botanical name. Beetroot, Swiss chard, sugar beet and fodder beet all belong to Beta vulgaris. They differ in the organs favored through generations of agricultural selection. ^{4 6}

Recognition

A table beet is most easily recognized by its single fleshy root, often dark red but sometimes white, yellow or ringed, depending on the cultivar. Above it sits a rosette of oval to heart-shaped leaves, dark green to reddish, on long and sometimes brightly colored stalks. ^{3 6}

Red table beet flesh and juice leave strong red stains, a useful clue. In the Cicla Group, or chards, the foliage dominates instead: large leaves and white, yellow or bright red stalks stand above a slender, fibrous root. ^{7 5}

During its first year, beet stays low, around 20 to 50 cm (8 to 20 in) tall. If left in the ground for a second year, it produces an upright, branched flowering stem, sometimes more than 1 m (3 ft) tall, with small greenish flowers in clusters. ^{3 4}

Useful taxonomy

The accepted scientific name, Beta vulgaris L., provides a consistent reference. Beet diversity falls into cultivar groups within one species, rather than separate species. Older names still circulate as synonyms or as the basis of these groups:

• Beta vulgaris subsp. vulgaris (accepted cultivated subspecies)
• Beta vulgaris var. maritima (L.) Moq. (sea beet)
• Beta vulgaris convar. cicla (L.) Alef. (chard)
• Beta vulgaris var. saccharifera Alef. (sugar beet)
• Beta vulgaris var. hortensis (Mill.) Alef. (garden beet)

Four main crop groups are useful in practice: Conditiva Group for table beet, Cicla Group for chard, Altissima Group for sugar beet, and a fodder group for livestock. These group names organize cultivated forms without creating new species. ^{1 7}

Habitat and range

Wild sea beet (Beta vulgaris var. maritima) is the ancestor of cultivated beets. It grows on cool, well-lit shores in western Europe and the Mediterranean basin. The natural range of the species extends from the Azores through western Europe and the Mediterranean to India. ^{3 1}

Gardeners and crop breeders selected this coastal plant for enlarged roots or abundant leaves. Beet is now cultivated on every temperate continent, in vegetable gardens and fields far beyond its Mediterranean and Atlantic homeland. ^{4 6}

For garden growing, beet favors moist, deep, rich soil in full sun. Salt tolerance inherited from its coastal ancestor lets it grow in soils that hinder other vegetables. Waterlogging remains a problem, however, because it causes root rot. ^{5 3}

Life cycle and reproduction

The biennial life cycle begins with a leaf rosette and storage of reserves in the root, the stage harvested in vegetable gardens. After a cold period, the plant bolts and flowers in its second year, then dies after fruiting. ^{3 4}

Small greenish flowers form clusters along the flowering stem. Those clusters explain how the crop propagates: each dry unit often contains several seeds, so one sowing point produces a clump of seedlings that needs careful thinning. ^{6 5}

Direct sowing takes place in spring to early summer, at 1 to 2 cm (0.4 to 0.8 in) deep in rows 25 to 30 cm (10 to 12 in) apart. Germination takes one to three weeks, depending on soil temperature, which should exceed about 7 to 10 °C (45 to 50 °F). Roots are harvested 8 to 12 weeks later, depending on the group; chard leaves can be picked progressively. Premature bolting often follows a cold spell affecting young plants and then a return to warm weather. ^{2 7}

Uses and risks

Food production is the main use of Beta vulgaris. The root is eaten cooked or grated raw, and the leaves are cooked like spinach. Depending on the group, this species supplies table beet, colorful chard stalks, large fodder roots for livestock, or sugar. ^{4 5}

The sugar beet has a distinct industrial role. Selected to contain 16 to 20% sucrose in its root, it became a major field crop in temperate regions and supplies a large share of sugar produced from sources other than cane. ^{5 4}

As a food plant, beet is nontoxic, including to cats, dogs and horses. The main caution concerns leaf oxalates, as in spinach: the leaves are useful greens, but moderation is advised for people prone to kidney stones. ^{5 7}

Varieties, look-alikes and related plants

Commercial beets are cultivars arranged in groups, rather than separate species. Conditiva covers table beets, Cicla chards and Altissima sugar beets, alongside fodder beets. Selections such as Bull's Blood and Bright Lights are horticultural names for plants valued for both ornamental and edible qualities. ^{6 7}

In vegetable gardens, the plants most likely to be confused are:

• Spinacia oleracea, spinach, another member of Amaranthaceae with oxalate-rich green leaves;
• Beta vulgaris var. maritima, wild sea beet, the ancestor of cultivated forms;
• young chard and table beet plants, which are difficult to distinguish before the root enlarges.

A fleshy root that stains red, a rosette of heart-shaped leaves and clustered seed units remain the most reliable clues that a plant belongs to Beta vulgaris. ^{3 1}

Main sources

• Plants of the World Online / Kew, Beta vulgaris L.
• Royal Horticultural Society, beetroot - grow your own
• Missouri Botanical Garden, Beta vulgaris
• Encyclopaedia Britannica, beet (Beta vulgaris)
• Plants For A Future, Beta vulgaris
• NC State Extension, Beta vulgaris Garden Beet Group
• NC State Extension, Beta vulgaris Leaf Beet Group