Module 4. Plant life cycles
Module 8. Pea life cycle Mystery
Pea life cycle
Peas
©Gwyneth Marsh 2007
How do they grow?
©Gwyneth Marsh 2007
Peas are the seeds of a plant.
They grow inside pods.
©Gwyneth Marsh 2007
The pea seeds we use to grow pea
plants are dry and hard, not like the
soft, green ones we eat.
©Gwyneth Marsh 2007
©Gwyneth Marsh 2007
pea seeds
peas we eat
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
©Susan Johnson 2007
©Gwyneth Marsh 2007
The pea plant is called a vine and
has tendrils which help it to climb as
it grows.
Tendrils
©Gwyneth Marsh 2007
Tendril
©Susan Johnson 2007
©Gwyneth Marsh 2007
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 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
© Susan Johnson 2007
Pea moths
lay eggs in
pea flowers
and, as the
pea pod
swells, the
grubs hatch
and eat the
peas inside
the pod.
Peas have nodules on their roots
Nodule
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.
© Susan Johnson 2007
This process is important
for organic growers who
rotate their crops and
keep the soil fertile
without using chemical
fertilisers.