Phaseolus coccineus, the runner bean or scarlet runner bean since most varieties have red flowers and multicolored seeds, though some have white flowers and white seeds, is a plant in the Fabaceae family. Runner beans have also been called "Oregon Lima Bean".and in Nahuatl "ayocotl" or in Spanish "ayocote". It differs from the common bean in several respects: the cotyledons stay in the ground during germination, and the plant is a perennial vine with tuberous roots (though it is usually treated as an annual). This species originated from the mountains of Central America.
The green pods are edible whole but in some varieties (the scarlet runner) tend to become fibrous early, and only the seeds within are eaten. The seeds can be used fresh or as dried beans. The starchy roots are still eaten by Central American Indians. In the UK, the flowers are often ignored, or treated as an attractive bonus to cultivating the plant for the beans, whereas in the US the scarlet runner is widely grown for its attractive flowers by people who would never think of eating it.
The flower is known as a favourite of Hummingbirds.
Runner beans contain traces of the poisonous lectin, Phytohaemagglutinin, found in common beans and hence must be thoroughly cooked before consumption.
Phaseolus coccineus subsp. darwinianus is a cultivated subspecies of P. coccineus, it is commonly referred to as the Botil bean in Mexico.
Aztec Half-Runner, also called "Potato bean"
White Dutch Runner