National Garden Bureau
Family
Fabaceae
Botanical Name
Phaseolus vulgaris
Plant Common Name
Bush Bean, Green Bean, Pole Bean, Shelling Bean, Wax Bean
General Description
Common beans, shelling, green or wax, are among the easiest of vegetables to grow successfully. These herbaceous annuals have two growth habits, bush and pole or climbing types, and originate from the tropical Americas.
Bean leaves are trifoliate (three-leaved), arranged in an alternate fashion on the stem and have oval or diamond-shaped leaflets. Leaf color can be green or purple. The flowers are typical of peas or beans; larger, rounded petals subtend smaller petals that form a lip or keeled beak. They are produced in loose clusters on short stalks among the foliage and can be white, pink or lavender.
Many modern bean cultivars are self-fertile. Their tasty edible pods are long and either flattened or rounded. The pods are filled with beans that are highly variable in shape and color, depending on cultivar. If harvested young the immature bean pods are eaten, as with green or wax beans. If allowed to mature, the dry, hard seeds can be shucked, stored and eaten at a later date, as with black beans or pintos.
Common beans are frost sensitive, so they should be planted after the danger of frost has passed and the soil has warmed. In cooler temperate climate they are grown as summer crops, whereas in warm, tropical zones beans are planted as fall and winter crops. All should be directly seeded because they do not transplant well. Overwatering seeds before germination can lead to seed rot, so be sure to keep them only moderately moist, never wet. Like many members of the bean family, common beans have a mutually beneficial relationship with a bacterium called Rhizobium, which allows plants to add nitrogen to the soil. Seeds and plants often do better if tossed in a commercially available Rhizobium inoculum before planting, but this step is not essential for success. Full sun and rich, friable, evenly moist soil with good drainage are needed for vigorous growth and fruit set.
Bush beans are compact, so they grow and produce well without support, whereas pole types are vines that can reach great lengths, so they require staking or other support. Beans produce usable crops quickly. Bush types flower approximately four to six weeks after seeding and immature bean harvest begins one to two weeks after flowering. Harvest them every few days. Dry beans are harvested when the pods dry and have changed to a brown or tan color, usually 60 to 70 days after germination.
There are hundreds of common bean varieties that vary widely in bean size, shape, production and color as well as plant size. Some are bred for northern climates and others for southern, so choose varieties that are better adapted to your growing area. If grown in the right climate they should be more pest-resistant and productive. Common beans are fun to grow, tasty and a great choice for novice, expert and children gardeners.