About Phaseolus coccineus L.
Phaseolus coccineus L., commonly known as runner bean, originated in the mountains of Central America, and was most likely first cultivated in the highlands of Mexico and Guatemala around 2000 BC. Most varieties have red flowers and multicolored seeds, though some have white flowers and white seeds, and the species is often grown as an ornamental plant. Its climbing vine can reach 3 metres (9.8 ft) or more in length; its pods can grow up to 25 centimetres (9.8 in) long, and its beans reach about 2.5 centimetres (0.98 in) long. It differs from the common bean (P. vulgaris) in multiple ways: during germination, its cotyledons remain underground, and the species is a perennial climbing vine with tuberous roots, though it is frequently grown as an annual in colder climates. The knife-shaped pods are normally green, but rare amateur-bred varieties have purple pods, with 'Aeron Purple Star' being one example of a purple-podded runner bean. Runner beans have also been called "Oregon lima bean"; they are known as ayocotl in Nahuatl and ayocote in Spanish. Like all beans, runner beans contain the toxic protein phytohaemagglutinin, so they should be cooked thoroughly before eating. From the 1600s onward, runner beans have been grown as both food plants and ornamentals for their attractive flowers in North America and Europe. In North America, they eventually came to be used primarily as garden ornamental plants, including for temporary screening. Their flowers attract hummingbirds, bees and other pollinating insects. In the United Kingdom and other European countries, where the plant is a popular crop for kitchen gardens and allotments, flowers are treated as an attractive bonus when growing the plant for its edible beans. The seeds of the plant can be used fresh or as dried beans. Young, still unfibrous pods are eaten whole, though their surface is rougher than that of common bean pods. The starchy roots of this perennial are eaten in Mesoamerica. The beans are used in many cuisines around the world. They are a popular side vegetable in British cuisine. In San Ildefonso, Spain, the variety 'Judión de la Granja' that produces large, white, edible beans is cultivated; these beans are the base of the Segovian regional dish Judiones de la Granja, where the beans are mixed with ingredients including pig's ears, pig's trotters, and chorizo. In Greece, runner bean cultivars with white flowers and white beans are called fasolia gigantes (φασόλια γίγαντες). They are grown under legal protection in the regions of Kato Nevrokopi, Florina and Kastoria in northern Greece. The beans play an important role in Greek cuisine and appear in many dishes, such as Gigantes plaki. In English, these large white beans are sometimes colloquially called elephant beans. In Austria, colored-seeded varieties are cultivated and served as "Käferbohnen" ("beetle-bean"), a dish made from dried runner beans with pumpkin seed oil. This is considered a typical dish of regional Austrian cuisine, and dried runner beans are also consumed to a small extent in Germany. In Turkey, runner beans are the main ingredient in the dishes bean Pilaki and Piyaz. During cold months, the runner bean pods sold as "green beans" in European markets come from Greece and northern Africa. These pods can be recognized by their flat shape, large size, and rougher surface. Listed cultivars of Phaseolus coccineus L. include: 'Aeron Purple Star' (not commercially available), 'Black Runner', 'Butler', 'Case Knife', 'Fasolia gigantes' (a white bean originating in Greece), 'Hammond's Dwarf', 'Japanese Runner' (sold in Canada and the USA under the names "Akahana" or "Shinshu runner"), 'Painted Lady', 'Pickwick Dwarf', 'Polestar', 'Scarlet Runner', and 'White Dutch Runner'. P. coccineus subsp. darwinianus is a cultivated subspecies, commonly called the botil bean in Mexico. The related species considered most useful for interbreeding with P. coccineus to increase its genetic diversity are P. dumosus and P. vulgaris.
