A seed consists of three main parts. The seed coat protects the seed’s insides. It is sturdy, and often covered with a waxlike material. The embryo contains the plant. The embryo is surrounded by the endosperm, which is the seed's food supply. The seed can be divided into sections, called cotyledons.

The hilum is a mark where the bean was once attached to a plant. Below it is the micropyle, the tube where the male nucleus first entered the ovule. The hypocotyl is the seedling’s root, while the epicotyl is its stem.

When a seed germinates, it swells with moisture, bursting the seed coat. This can happen because the seed has a shortage of food, or because the coat has been ruptured by an outside source. Some species will not use their endosperm until germination begins, and will therefore remain dormant unless the seed coat is broken. 300-year-old lotus seeds, found in dry Chinese soil, grew after their seed coats were punctured.

Lima beans grow in pods on a variety of plant forms: some are pole beans, while others grow on both bushes and vines. The beans within the pod will grow until they break open the pod. They will then be dispersed.

Growth of a Lima Bean