How Tall Can the Pigeon Pea Tree Grow?

Climate

• Pigeon pea grows best at temperatures ranging from 64 to 86 degrees Fahrenheit. It can survive a dry season of more than six months, although it grows best with 24 to 40 inches of rain annually. Pigeon pea loses its leaves in frost. It is hardy in frost-free U.S. Department of Agriculture plant hardiness zones 10 and warmer; it is grown in Hawaii, Florida and Puerto Rico. The cultivar “Amarillo” (Cajanus cajun “Amarillo”) can be grown and harvested throughout the year in Florida.

Soil

• Although pigeon pea grows in all kinds of soil, it does best in a well-drained, medium-heavy loam. Loam contains roughly equal amounts of sand, silt and clay. The shrub grows in a wide range of climates, from moist to wet, warm temperate zones to wet forests and tropical deserts. Because it is a legume, pigeon pea is nitrogen-fixing, which means it has a symbiotic relationship with bacteria that live in nodules on the shrub's roots. The bacteria produce nitrogen that helps the pigeon pea compete with other plants that obtain their nitrogen from the soil. When a pigeon pea dies, its nitrogen is released into the soil, and other plants use that nitrogen.

Life Cycle

• A pigeon pea sprout should emerge from soil two to three weeks after a seed was sown. The plant grows slowly at first, but growth accelerates when the plant is 2 to 3 months old. It typically begins flowering from four to five months after it is planted, and its seeds mature in about eight months, although flowering can begin as early as two months and seeds can mature as early as 100 days. Because a pigeon pea's yield declines after the shrub's first year and plunges after its third year, the shrub typically is grown as an annual or biennial. Farmers who grow the shrub for animal forage usually clear it out after five years. A pigeon pea dies naturally when it is roughly 10 to 12 years old.

Edible Seeds

• The occasionally hairy pigeon pea pods are usually green but are sometimes dark purple or green streaked with purple. They contain two to nine seeds. Pigeon pea is popular in the food of tropical countries. Although sometimes the pods and immature seeds are eaten, more often dried mature seeds are eaten as dahl, a kind of split pea, in soups or with rice. In order to eat pigeon pea as a vegetable, pick its pods when the pods' seeds are fully mature but before the seeds' green coloring begins to fade. Split pigeon pea seeds are 21 to 28 percent protein, similar to soybeans' protein percentage.