Remember the story of Jack in the Beanstalk?  He climbed a beanstalk that grew so high he was able to capture a goose that laid golden eggs from a mean king who lived in a magic castle in the heavens and saved Jack and his mother from starvation.  The Jack bean (Canavalia ensiformes) inspired this story.  The hardy climbing perennial vine can easily grow rapidly to reach a height of at least six feet or taller.  Jack beans are commonly planted as an annual crop for use as an animal fodder, as human nutrition and as a valuable soil builder.

Jack beans are native to the West Indies, Central America and tropical Africa and thrive in hot humid climates world-wide.  They grow well in heavy rainy areas and are able to survive in droughts and tolerate mildly saline conditions.  Jack Beans are also known as 'wonder beans' and are sometimes confused with sword beans (Canavalia gladiata) as the plants are similar.  Both are easy to grow and require minimal care to produce high amounts of biomass.
 

The plants grow best on long poles tipi style or on a trellis and require at least six hours of sun daily. Seeds can be planted approximately  4-5 inches apart around each poles and covered with about 1 and ½ to 2 inches deep and watered until the shoots are established and starting to climb the poles.  They also make a great ground cover when allowed to sprawl minus poles as a green manure cover crop.  The recommended pH for the soil is 5.5 – 6.0.  Jack bean vines flower in about 6 weeks after planted, Pods take anywhere from 80 – 120 days to reach maturity.  The pods develop to be anywhere from about 1 foot to 2 feet in length and the pods turn brownish when ripe.  Each pod is filled with large white seeds.  The pods on the vines is our garden contain about 12 seeds each. 

The pods of bean plants and the leaves can be boiled and eaten as a vegetable without any special precautions.  Once the pods mature and create seeds in the pods, complicated directions must by followed to make them edible for human consumption.  These directions include; soaking the beans for one day then washing them every morning and night for 2-4 days until they are sprouted with a tail, then boiling the seeds until they are tender at least twice after rinsing and changing the water.  It may be safer to allow jack bean vines and seeds to be used as a green manure or cover crop rather than a food source.  Plants and seeds detoxify enough to be used as animal fodder after 3 days of being spread on a tarp in the hot sun.  Animals should be gradually introduced by offering small amounts of jack bean plant vines, leaves and seeds.

Jack beans reputation as 'wonder beans' is well earned.  The roots suppress nematodes, while fixing nitrogen in the soil, pods and vines are rich in protein. Jack bean vines help to keep animals out of gardens as animals avoid the raw plant toxins. Properly processed, they produce fodder for animals and the beans are roasted as a coffee substitute in Cuba and parts of Africa.

The plants are resistant to ants, including leaf cutter ants.  (It is claimed that placing jack bean vine leaves on top of leaf cutter ant hills  for 3 days in a row will eliminate the colony.) and are not bothered by locusts. They are considered to be an 'emergency crop' when other crops fail as the plants can be toxic for humans to eat unless they are carefully prepared.  Jack beans are a helpful companion plant and fit well with regenerative gardening and farming practices.

Consuming Jack Beans:

While improving soil quality, the Jack bean is also an effective deterrent to garden pests. Though Jack beans can be an excellent food source, especially in periods of drought, these same compounds in the plant that make the bean inedible to insects, can be toxic to humans without special precautions.