Canavalia ensiformis
Origin: Mesoamerica, Colombia & Venezualia, via India
Improvement status: Unknown
Seeds per packet: 10
BOTANICAL SAMPLE - NOT GERMINATION TESTED
Life cycle: Tender perennial (grown as annual in temperate regions)
Also called "sword bean," jack beans are large white-seeded tropical perennial legumes native to Mesoamerica, Colombia, and Venezuela. We first encountered the plant in a student agroecology garden on the campus of the University of Puerto Rico at Rio Piedras, where the students excitedly told us it is grown as a nitrogen-fixing companion plant (see last photo). It's called "sword bean" for its long, broad, edible seed pods (best when still tender and young), which can grow to 14 inches long, though another closely-related species, Canavalia gladiata, is more often called "sword bean" and has even bigger seeds and pods. The seed coats are generally removed before eating the beans, as one might with fava beans. The beans are mildly toxic until they have been boiled properly. Young leaves are also edible.
This species has been adopted by farmers in various other parts of the world, including India, the Philippines, Zambia, Senegal, Ethiopia, Peru, and especially Brazil, where it's called feijão-de-porco ("pig bean"). Despite this popularity, it is still a rarely seen here in the US. Jack bean is far more productive when grown as a perennial in the tropics — it becomes a shrubby 6+ foot bush over time, with some types more viny — but it matures quickly enough that it can be grown as an annual in much of North America. When we've grown it in New Jersey, each plant typically makes just 2 to 4 pods, but that's enough for quite a lot of food. There's something just plain marvelous about growing such an enormous bean-pod in a single season.
GROWING TIPS: Direct sow once soil has warmed, at the same time you would string beans or corn, in a good weed-free bed.
