Scientific Name: Phaseolus lunatus

AKA: Madagascar Bean, Tropical Lima Bean, Butter Bean

Synnonyms: Phaseolus limensis

Family: Fabaceae (Pea)

Etymology:

Phaseolus: Bean; Greek
lunatus: Moon-Shaped; Latin

Origin:

The species Phaseolus lunatus is of Andean and Mesoamerican origin.  The domestication of large seeded lima beans first occurred in the Andes around 2000 years ago.

Description:

A vigorous climbing tropical bean, this variety has white seeds with attractive purple speckling.  It is particularly suited to hot, humid conditions.  It's a perennial, dying back during Winter.  Production may be limited in its first year, it produces higher yields in subsequent years.  Each pod contains 1-3 large (~2cm) seeds.

Uses:

Young seeds can be peeled and eaten raw or steamed, as long as they haven't yet started to developed any of their mottled red colouration.  Young green pods can also be steamed but can be fibrous.  Older, dried and shelled seeds can be soaked overnight then boiled until soft, drained and used in any dish you would normally use shelled beans in.  The sprouted seeds are used in Chinese cooking.  The youngest leaves are also edible but have a bitter flavour and definitely should be cooked prior to eating.  Some varieties of lima bean can contain dangerous levels of cyanogenic glucosides, which can be deactivated by soaking, boiling, draining, and peeling the skin off the seeds.  This particular variety is thought to be largely free of these toxins however care should still be taken to prepare them correctly as there are other, less potent toxins present too.  Stored dried shelled seeds can be frozen for 48 hours to kill any bean weevil eggs.

Germination:

Requires a warm soil temperature to germinate, at least 18.3 degrees Celsius.  Best sown directly where they are to grow, 3-4cm deep and 60cm apart.  Does best in all areas when sown during Spring, 3-4 weeks after the last frost has past in temperate areas.

Cultivation:

Benefits from trellising, choose something strong that can cope with vigorous growth and make sure support wires are not too far apart otherwise the runners may have trouble climbing to the next rung.  May only grow as an annual in temperate areas.  Likes well-drained soils. Takes 12-15 weeks untill first harvest.