Annual Plants
The stages of growth for this annual plant are as follows:
- The bean remains dormant until temeratures are warm enough for germination in spring - about 15-20 degrees C. If it is planted in a moist, warm well-drained and nutritive soil, beans begin to sprout in 2-3 days.
- The process of sprouting begins with swelling of the bean, due to water getting into the seed and swelling the bean until the seed coat splits and the radicle emerges out.
- The bean has hypogeal growth meaning the cotyledons stay in the ground providing food for the growing plant and the first green stems to emerge are true leaves. Once the little plumule grows out it begins to grow upwards and straightens so that it can grow upwards and develop into leaves.
- The bean plant grows into a mature bean plant in about 6 weeks. It then enters the reproductive stage and starts flowering.
- Bean plants have bisexual flowers, that is, the flowers have both, male and female reproductive organs.
- The start of the reproduction to make more beans is pollination. The pollen grains fall on a receptive stigma, of the same flower or on that of another bean plant.
- Once the pollen grains attach to the stigma, they germinate, and a pollen tube is formed. This pollen tube extends through the style, into the ovary. The sperms travel through this pollen tube and enter the ovary.
- Beans have a special way of forming. The zygote, inside the ovary, grows by utilizing the nutrients from the endosperm, and develops into beans, whereas the ovary grows into the pod.
- At first the beans are delecate and green, but gradually they dry and h