To grow a plant from seed, plop it in the ground, water it, and wait, right? Well, it depends. Many seeds have mechanisms that keep them dormant until the right time of year or environmental conditions are suitable. Depending on the kind of seed, you may have to scarify it or stratify it or both. Huh? Well, let's take scarify first. Some seeds have seed coats that can't be penetrated by water or gases. In nature, the weather or microbial activity or passage through the digestive system of an animal degrades the seed coat and allows germination. A person can achieve similar results with a file or sandpaper or by soaking the seed in an acid, such as vinegar. The seed is then ready to plant.
In stratification, the seeds are subjected, sometimes for months, to
cool, moist conditions at about 40°F or warm, moist conditions--again, depending on the
species of plant. And then there are the real toughies that require scarification and
stratification. Prescription for de-stressing? Get out there and scarify and stratify
to your heart's content!
Listen to the Audio (mp3 format) as recorded by KTEP, Public Radio for the Southwest.
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.