Plant 255

Cucurbita species (Cucurbitaceae)


Cucurbita is a small genus native to Central and South America, and contains several species that were independently domesticated for food, and other uses, across the Americas and were essential parts of human food economies before European contact. Pumpkins, courgettes and marrows are derived from Cucurbita pepo, whilst giant pumpkins and butternut squashes are derived from Cucurbita maxima.

Some of these species have become familiar outside of the Americas because of the high diversity of fruit shapes that they produce. For example, fruits can vary in colour from green and yellow to orange and even shades of blue with skins that may bear warty protuberances.

Cucurbita maxima is a trailing herbaceous, annual vine with tendrils, although some cultivated varieties have a compact, bushy habit. Individual plants of Cucurbita maxima have large, separate, yellow, male and female flowers; the plants are monoecious. The species' thick, soft and corky fruit stems are distinctive. Despite being intolerant of frost, its rapid growth ensures Cucurbita maxima produces abundant fruit in one temperate growing season.

Cucurbita maxima originated from Cucurbita andreana, a species native to Uruguay and Argentina, and was domesticated about 4,000 years ago. Along with other members of the genus, Cucurbita maxima was an important crop plant in the societies of pre-Columbian Central and South America. Today, this plant is widely cultivated across the planet.

Of the many cultivated Cucurbita maxima varieties, 'Buttercup', 'Hubbard' and 'Banana' are particularly popular, and their tasty fruits can be stored for very long periods. The fruits have many culinary uses, both savoury and sweet, the flesh being low in calories but rich in protein, minerals and vitamin A.

The seeds of Cucurbita maxima are edible, producing a nutrient-rich oil. Traditionally, seeds are used as vermifuges and for the treatment for ulcers on the skin.

Several varieties of Cucurbita maxima have been selected to produce very large fruit and competitions to grow the largest are popular in the USA and parts of Europe. The world record is a pumpkin weighing 1.19 tonnes, which was grown in Belgium in 2016. Growers use varieties such as 'Atlantic Giant' to produce large plants, which are then pruned to leave only one fruit. Huge quantities of water and nutrients are essential to grow such enormous fruit. However, the quality of such giant fruit for eating is usually very poor, and they are often hollowed out to make decorations or even novelty boats.

Further reading

Organ J 1963. Gourds. Faber and Faber.

Ott C 2012. Pumpkin: the curious history of an American icon. University of Washington Press.

Sanjur OI et al. 2002. Phylogenetic relationships among domesticated and wild species of Cucurbita (Cucurbitaceae) inferred from a mitochondrial gene: implications for crop plant evolution and areas of origin. Proceedings of the National Academy of Sciences 99: 535-540.

James Penny