Cucumber

Cucumber, Cucumis sativus, is a warm season, vining, annual plant in the family Cucurbitaceae grown for its edible cucumber fruit. The cucumber plant is a sprawling vine with large leaves and curling tendrils. The plant may have 4 or 5 main stems from which the tendrils branch. The leaves of the plant are arranged alternately on the vines, have 3–7 pointed lobes and are hairy. The cucumber plant produces yellow flowers that are 4 cm (1.6 in) in diameter. The cucumber fruit varies in shape but is generally a curved cylinder rounded at both ends that can reach up to 60 cm (24 in) in length 10 cm (3.9 in) in diameter. Cucumber plants are annual plants, surviving only one growing season and the vines can reach up to 5 m (16.4 ft) in length. Cucumber may also be referred to as gherkin and originates from the foothills of the Himalayas, likely in India.


Although technically a fruit, cucumbers are used as a fresh vegetable, consumed fresh in salads. Some varieties are grown specifically for pickling. Yellow varieties are generally cooked before consumption.


Basic requirements Cucumbers require warm, dry conditions to develop optimally, preferring both warm days and warm nights and growing best at a temperature of 30°C (86°F). Cucumbers will yield best if grown in a fertile, well-draining soil, rich in organic matter and with a pH between 6.5 and 7.5. Cucumbers are very sensitive to cold and should be planted in full sun and provided with ample soil moisture due to their shallow root system. Cucumber varieties One of the biggest considerations when choosing a cucumber variety is whether or not it requires pollinating. Many newer cucumber varieties are gynoecious which means that they produce only, or mostly, female flowers. Some gynoecious varieties require pollinating with male flowers, in which case a proportion of the seeds in the packet will be pollinator plants which produce the male flowers. Some gynoecious varieties are parthenocarpic which means that they do not need the male plants to produce fruit. These types are recommended for growing in glasshouses as they do not require the presence of insect pollinators. Sowing seeds Direct seeding is the preferred method for sowing cucumbers as they do not transplant well. Seeds should be sown after the last frosts and when the soil has warmed to at least 15.6°C (60°F). Sow seeds 1.3–2.5 cm (0.5–1.0 in) deep, thinning to a spacing of at least 30 cm (12 in) between plants after germination. Cucumbers can also be seeded on hills or mounds of soil to encourage warm soil and better drainage. In this instance, seeds should be sown on hills in groups of 4–6 seeds, allowing 1.2 m (4 ft) between each group in all directions. After emergence, thin the seedlings to 1 or 2 plants per hill. Cucumber seeds should germinate in 4–13 days depending on the soil temperature. General care and maintenance Cucumber vines are sprawling and require plenty space to grow. Vines can be trained to grow on a trellis or fence. Providing burpless varieties with vertical support allows the fruits to hang loose and grow straight. Cucumbers also require a continuous supply of water and where drip irrigation is not being used, plants should be watered deeply once per week, providing at least an inch of water. Shallow watering or watering less frequently will reduce fruit yields. Mulches can be used to conserve soil moisture and black plastic mulch has the advantage of warming the soil. Harvesting Cucumbers should be harvested from the plant when they are still immature and green in color. Mature fruits are yellow and the flesh is often tough with woody seeds. The size of cucumbers at harvest depends on the variety of the cucumber being grown and what it is to be used for. Cucumbers for pickling are generally picked when they are less than 5 cm (2 in) long whereas burpless cucumbers for slicing should be allowed to reach approximately 4 cm (~1.5 in) in diameter. It is important to remove any fruits nearing maturity to ensure the plant remains productive. Their rapid growth means that cucumbers may need harvested every couple of days.


CABI Crop Protection Compendium. (2008). Cucumis sativus datasheet. Available at: http://www.cabi.org/cpc/datasheet/16967. [Accessed 19 November 14]. Paid subscription required. Coolong, T. (2010). Cucumber. University of Kentucky Cooperative Extension Service. Availabel at: http://www.uky.edu/Ag/NewCrops/introsheets/cucumber.pdf. [Accessed 19 November 14]. Free to access. Lerner, B. R. & Dana, M. N. (2001). Growing Cucumbers, Melons, Squash, Pumpkins and Gourds. Purdue University Cooperative Extension Service. Available at: http://www.hort.purdue.edu/ext/ho-8.pdf. [Accessed 19 November 14]. Free to access. Zitter, T. A., Hopkins, D. L. & Thomas, C. E. (1996). Compendium of Cucurbit diseases. American Phytopathological Society Press. Available at: http://www.apsnet.org/apsstore/shopapspress/Pages/42074.aspx. Available for purchase from APS Press.