Tropical American native that generally resembles pole bean in form and foliage. The spring-to-summer flowers are different, though: fragrant, cream to pale purple, with lilac or purple markings and twisted keel petals that are coiled like a snail shellodd and pretty. Twines rapidly to 1020 feet.; good summer screen or bank cover. A favorite of Thomas Jefferson at Monticello. Evergreen in Tropical South; in colder regions, treat as annual or bring indoors for winter. Sometimes sold as Phaseolus gigantea. Formerly known as Phaseolus Caracalla.