Cucumber Crop Information
- by Todd C. Wehner
- Department of Horticultural Science
- North Carolina State University
- Raleigh, NC 27695-7609
Cucumber, Cucumis sativus, is the fourth most important vegetable crop in the world and the most important cucurbit. Cucumbers, like most cucurbits, are indeterminate, vining (1–3 m), frost-sensitive annual plants that produce cylindrical or round fruit. Determinate cultivars, generated from a naturally occurring mutation in gibberellin sensitivity, were first introduced with ‘Midget’ in 1940, and have been used in home gardens and patio containers. Usually, a single, unbranched tendril develops at each leaf axil, although a tendrilless (tl) mutant has been described. The stems, leaves, and young fruit of the plants are covered in stiff, multicellular, unbranched trichomes. The leaves of this species are triangularly ovate, with 3–5 lobes. Early cucumber cultivars were monoecious, but gynoecious, androecious, hermaphroditic, gynomonoecious, andromonoecious and trimonoecious forms are also present in this species. Little variation in petal color or shape has been observed in cucumber. Flowers are yellow with five or six basally fused petals. Plants often produce male flowers initially (first 3 nodes) followed by alternating male and female flowers, and finishing with mostly female flowers. Flowers remain open for a single day and are pollinated by bees and other insects. Immature fruit are green at the edible stage, except in a few cultivars, where they are white or yellow. Fruit are round to oblong or narrowly cylindrical, with small tubercles (warts) and spines of trichome origin on the rind. Spine colour is associated with mature fruit colour and fruit netting. Fruit of white-spined cultivars are light green to yellow at maturity and not netted. Black-spined fruit become orange or red (brown) when mature and may be netted. Fruit flesh is crisp and usually white, but is pale orange in a few cultivars. Seeds are small, white and flat.
Most cultivars have long vines, and are grown flat on the ground for pickling and slicing type cultivars, or on trellis supports for Oriental and greenhouse types. Plants are normally monoecious (separate staminate and pistillate flowers), but most modern cultivars are gynoecious (female) hybrid blends (12 to 15% of the seeds are a monoecious pollenizer). Plants require various insects, especially bees, to effect pollination. Cucumber is grown for its fruit, which are eaten fresh or pickled, or fried (usually when fruit have been harvested at a more mature stage). The fruit have a high water content, and they provide some vitamin A and C, especially when pickled with dill and other spices. Per capita annual consumption of fresh cucumber is 3.1 kg and processed cucumber 2.2 kg in the United States.
Cucumber (Cucumis sativus L.) is thought to have originated in India where it is found wild and is cultivated in many diverse forms. Accessions of C. sativus var. hardwickii may be more closely related to the original ancestors of cucumber, and have been collected in the foothills of the Himalaya Mountains. Secondary centers of diversity for cucumber exist in China and the Near East. Cucumber was probably domesticated in Asia, and then introduced into Europe, where the first cultivars were selected in the 1700s. Cucumbers were brought to the Americas by Christopher Columbus, and Native Americans were growing cucumbers from Florida to Canada by the early 16th century. Related species are Cucumis hystrix from China, and the African Cucumis species, such as melon (Cucumis melo), gherkin (Cucumis anguria), and their wild relatives. About 80% of the world production of cucumber is in Asia, with China being the leading producer.