What Happens If a Seed Doesn't Germinate?

Germination

• Plants start as embryos in the germ layer of a seed; hence the term "germination," meaning the successful emergence of a plant embryo through the germ layer. If seeds don't experience a successful pollination, the seed is not viable and the embryo cannot develop properly and grow into a plant. Human intervention cannot overturn these dictates of nature and make a plant grow. However, there are circumstances when human intervention or favorable environmental stimulation can influence successful germination.

Manipulating Growing Conditions

• Many undesirable environmental conditions exist when gardeners sow seeds directly into the garden. Too much or too little light and water, incorrect sowing depth and predators that eat seeds adversely affect seed germination. In a controlled indoor environment, gardeners sow seeds in containers so that they can regulate light, water, planting depth and obtain isolation from predators. Seeds have higher germination rates and gardeners have the satisfaction of starting their plants from seeds. When seedlings are strong enough, gardeners simply transplant them into their gardens.

Scarification

• Sometimes what causes seeds not to germinate is structural. Their hard outer seed coats are impermeable to water and gases, and without these nutrients they lay in a state of dormancy. The seeds that fall from plants and spend the winter outdoors experience heaving; or periods of alternate freezing and thawing. This natural process splits hard seed coats and allows water and gases to enter. Imitating nature, gardeners employ scarification, scarring a seed coat by filing, nicking, or sanding.

Stratification

• Another factor that causes some seeds not to germinate is their need for chilling. In nature, cold stratification occurs when plants drop seeds in autumn and they winter outside. When gardeners buy seeds in packets, they store them under warm indoor conditions without giving them a chilling period. Placing seeds in the refrigerator to mimic winter conditions and then sowing in warm temperatures triggers the end of a dormant period. Germination is the successful result of cold stratification.