Module 4. Plant life cycles Module 8. Pea life cycle Mystery

Peas ©Gwyneth Marsh 2007 How do they grow?

Peas are the seeds of a plant. They grow inside pods. ©Gwyneth Marsh 2007 ©Gwyneth Marsh 2007

The pea seeds we use to grow pea plants are dry and hard, not like the soft, green ones we eat. Teachers should be aware that we do eat some ‘dried’ peas. We often buy them as ‘pulses’; these usually need soaking overnight and are then added to soups and stews. ©Gwyneth Marsh 2007 ©Gwyneth Marsh 2007 pea seeds peas we eat

The pea seeds germinate when they absorb water and become softer The pea seeds germinate when they absorb water and become softer. A small root grows first, then a small shoot. Shoot Root ©Gwyneth Marsh 2007

The root grows first. It anchors the plant and absorbs water from the soil. The shoot can then grow into a seedling Pea seedlings ©Gwyneth Marsh 2007 ©Susan Johnson 2007

The pea plant is called a vine and has tendrils which help it to climb as it grows. ©Gwyneth Marsh 2007 Tendril ©Susan Johnson 2007 ©Gwyneth Marsh 2007

Garden peas usually have white flowers Garden peas usually have white flowers. Bees may visit the flowers, but peas can self-pollinate. ©Gwyneth Marsh 2007

Once the pea flowers are pollinated the pods begin to grow. ©Gwyneth Marsh 2007 ©Gwyneth Marsh 2007 ©Gwyneth Marsh 2007

We harvest the peas to eat when the pods are fat and green. ©Gwyneth Marsh 2007 ©Gwyneth Marsh 2007

We can save seed to grow peas again next year We can save seed to grow peas again next year. We must let the pods ripen and dry on the vine. We harvest them and take out the seeds. ©Gwyneth Marsh 2007 ©Gwyneth Marsh 2007

Pea moths Pea moths lay eggs in pea flowers and, as the pea pod swells, the grubs hatch and eat the peas inside the pod. © Susan Johnson 2007

Peas have nodules on their roots The nodules contain bacteria that take in nitrogen from the air and enrich the soil to help the plant grow. When the plant dies and decays nitrogen is also released into the soil. This process is important for organic growers who rotate their crops and keep the soil fertile without using chemical fertilisers. © Susan Johnson 2007