Germination is the process by which a plant grows from a seed into a seedling. Seeds remain dormant until conditions are favorable for germination. All seeds need water, oxygen and optimal temperature to germinate.
When a seed is exposed to the proper conditions, water and oxygen are taken in through the seed coat. The embryo’s cells start to enlarge. Then, the seed coat breaks open and the root emerges first, followed by the shoot that contains the leaves and stem.
Sunlight supports the germination process by warming the soil. Although uncommon, some seeds need direct contact with sunlight to germinate. Once leaves have sprouted, sunlight is the primary energy source for plant growth through the process of photosynthesis.
A seed has everything it needs to begin a new life. Inside the seed coat, is an embryonic (baby) plant composed of an embryonic root, stem and leaves. In addition, the seed contains a food supply – called the endosperm – that is packed with nutrients to keep the seed nourished and allow it to grow.
As the embryonic plant develops, the seed leaves, or cotyledons, absorb the food supply and continue to nourish the plant. Once the leaves appear, the plant begins to make its own food through photosynthesis.
With their seed coats protecting the delicate plant embryos within, seeds are unique structures. Many seeds are able to endure long periods of drought, heat or freezing temperatures, yet are ready to spring to life when favorable conditions arise.