Taxonomic history Both written history and molecular genetic studies indicate that the domestic carrot has a single origin in
Central Asia. Wild carrots were presumably
bred selectively in the region of origin over the centuries to reduce bitterness, increase sweetness and minimise the woody core. This process produced the familiar garden vegetable. The domestic carrot is classified as its own
subspecies D. carota subsp.
sativus,
History , a 6th-century AD copy of
Dioscorides' 1st-century pharmacopoeia. The facing page states that "the root can be cooked and eaten." When first cultivated, carrots were grown for their aromatic leaves and seeds rather than their roots. Carrot seeds have been found in
Switzerland and
Southern Germany dating back to 2000–3000 BC. Some close relatives of the carrot are still grown for their leaves and seeds, such as
parsley,
coriander (cilantro),
fennel,
anise,
dill and
cumin. The first mention of the root in classical sources is from the 1st century AD; the Romans ate a root vegetable called
pastinaca, which may have been the carrot or the closely related
parsnip. The plant is depicted and described in the
Eastern Roman Juliana Anicia Codex, a 6th-century AD
Constantinopolitan copy of the Greek physician
Dioscorides' 1st-century pharmacopoeia of herbs and medicines, . The text states that "the root can be cooked and eaten". Another copy of this work, Codex Neapolitanes from the late 6th or early 7th century, has basically the same illustrations but with roots in purple. The plant was introduced into Spain by the
Moors in the 8th century. In the 10th century, roots from West Asia, India and Europe were purple. The modern carrot originated in
Afghanistan at about this time. as does the 12th-century Arab-
Andalusian agriculturist,
Ibn al-'Awwam. Cultivated carrots appeared in China in the 12th century, and in Japan in the 16th or 17th century. The orange carrot was created by Dutch growers. There is pictorial evidence that the orange carrot existed at least in 512 AD, but it is probable that it was not a stable variety until the Dutch bred the cultivar termed the "Long Orange" at the start of the 18th century. Some claim that the Dutch created the orange carrots to honor
the Dutch flag at the time and
William of Orange, but other authorities argue these claims lack convincing evidence and it is possible that the orange carrot was favoured by the Europeans because it does not brown soups and stews as the purple carrot does and, as such, was more visually attractive. European settlers introduced the carrot to
colonial America in the 17th century.
Propagation , California, 1948 Carrots are grown from seed and can take up to four months (120 days) to mature, but most cultivars mature within 70 to 80 days under the right conditions. They grow best in full sun but tolerate some shade. The optimum temperature is . The ideal soil is deep, loose and well-drained, sandy or loamy, with a
pH of 6.3 to 6.8. Fertilizer should be applied according to soil type because the crop requires low levels of nitrogen, moderate phosphate and high potash. Rich or rocky soils should be avoided, as these will cause the roots to become hairy and/or misshapen. Irrigation is applied when needed to keep the soil moist. After sprouting, the crop is eventually thinned to a spacing of and weeded to prevent competition beneath the soil.
Pests and diseases is a pest of carrot crops. Among pests of carrot crops is the
carrot fly (
Chamaepsila rosae), a
dipteran fly in the family
Psilidae. Its
maggot larvae eat the outside of the root, damaging the crop. There are several diseases that can reduce the yield and
market value of carrots. The most devastating carrot disease is
Alternaria leaf blight, which has been known to eradicate entire crops. A bacterial leaf blight caused by
Xanthomonas campestris can also be destructive in warm, humid areas. Root knot nematodes (
Meloidogyne species) can cause stubby or forked roots, or
galls.
Cavity spot, caused by the
oomycetes
Pythium violae and
Pythium sulcatum, results in irregularly shaped, depressed lesions on the taproots. Physical damage can also reduce the value of carrot crops. The two main forms of damage are splitting, whereby a longitudinal crack develops during growth that can be a few centimetres to the entire length of the root, and breaking, which occurs postharvest. These disorders can affect over 30% of commercial crops. Factors associated with high levels of splitting include wide plant spacing, early sowing, lengthy growth durations, and
genotype. Carrots can be good companions for other plants; if left to flower, the carrot, like any
umbellifer, attracts predatory wasps that kill many garden pests.
Cultivars Carrot
cultivars can be grouped into two broad classes: "Eastern" carrots and "Western" carrots. A number of novelty cultivars have been bred for particular characteristics. , a Japanese cultivar from
Kyoto Prefecture The "Western" carrot emerged in the
Netherlands in the 16th or 17th century. There is a popular claim that its orange colour made it popular in those countries as an emblem of the
House of Orange and the struggle for
Dutch independence, although there is little evidence for this beyond oral tradition and the timing. • Imperator. This cultivar has vigorous foliage, is of high sugar content, and has long and slender roots, tapering to a pointed tip. Imperator types are the most widely cultivated by commercial growers. One particular cultivar lacks the usual orange pigment due to carotene, owing its white colour to a
recessive gene for
tocopherol (vitamin E), but this cultivar and wild carrots do not provide nutritionally significant amounts of vitamin E.
Storage Carrots can be stored for several months in the refrigerator or over winter in a cool dry place. For long term storage, unwashed carrots can be placed in a bucket between dry layers of sand, a 50/50 mix of sand and wood shavings, or in soil. A temperature range of and 90–95% humidity is best. During storage, carrots may be subject to the development of bitterness, white blush, and browning, leading to carrot losses. Bitterness can be prevented by storage in well-ventilated rooms with low
ethylene content (for example, without ethylene-producing fruit and vegetables). White blush and browning can be countered with application of edible films, heat treatment, application of
hydrogen sulfide, and ultraviolet irradiation.
Production In 2024, world production of carrots (combined with
turnips) was 45 million
tonnes, led by China with 42% of the total.
Uzbekistan, Russia, and the United States were the only other countries producing over 1 million tonnes annually (table). == Uses ==