Germination
Seeds remain dormant or inactive until conditions are right for germination. All seeds need water, oxygen, and proper temperature in order to germinate.
Some seeds require proper light also. Some germinate better in full light while others require darkness 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 a root or radicle emerges first, followed by the shoot or plumule that contains the leaves and stem.
Many things can cause poor germination. Overwatering causes the plant to not have enough oxygen. Planting seeds too deeply causes them to use all of their stored energy before reaching the soil surface. Dry conditions mean the plant doesn't have enough moisture to start the germination process and keep it going.
Some seed coats are so hard that water and oxygen cannot get through until the coat breaks down. Soaking or scratching the seeds will help break down the seed coat. Morning glories and locust seeds are examples. Other seeds need to be exposed to proper temperatures. Apple seeds will not germinate unless they are held at cold temperatures for a period of time.
Do all plants use seeds to reproduce? When you're finished, click here to find out!
