Life Cycle of a Broad Bean Seed

The broad bean is one of the most ancient plants in cultivation and also one of the easiest to grow. It is also known as fava bean, horse bean, field bean, Mexican bean and tic bean. Broad bean plants grow 2 to 3 feet high, with many branches off the main stem. They grow in full sun. They are an annual legume with seed pods up to 15 inches long. Plant seeds in early spring, 1 inch deep and 6 inches apart.

Beginning Life Cycle

The broad bean is an annual plant that completes its growth cycle in one growing season. Plant broad beans early in spring. Plant seeds in compost-rich soil for best growth, although the plants are tolerant of many soil conditions. Water the seeds and soon they will soften and begin to open underground. The bean seeds are generally 1 inch in length and oval-shaped.

Seeds Split Open

Small shoots grow out of the split seed as it sheds its outer coat. One shoot grows toward the soil top, reacting to sunlight and water. It is called the hypocotyl. A primary root begins to grow, with smaller secondary roots as offshoots. Soil nutrients feed the tiny roots and new sprouts as they grow. Within the seed is an embryonic leaf called the cotyledon.

Flowers

As the plant matures, flowers appear on stems. Each leaf stem produces two to four flowers. A normal field bean plant has 50 to 80 flowers. These will become the broad bean seed pods. The plant will shed most of these and grow on average a dozen pods per plant. The flowers are white and the wing-petals have a deep purple spot. Heritage varieties have crimson flowers.

Seed Pods

Seed pods develop as the flowers fade and wither on the plant. They are a broad, leathery pod with a downy surface, maturing green to brownish-black. Seeds mature in a round to oval shape, three to eight to a pod. Broad beans grow to maturity in 4 to 5 months. Their seed pods grow from 2 to 15 inches long. Each pod contains three to eight seeds.

Harvest

Beans will be ready to harvest in 80 to 100 days. Plants are best sown in fall for a spring harvest. They like cool weather and don’t do well at high temperatures. The harvest will be approximately a dozen seed pods from each plant, each pod containing two to eight broad beans. Harvest seed pods as they mature, just a few at a time.