Scarification (botany): The process of damaging a tough seed coating to hasten germination. It can be accomplished with thermal stress, extended soaking, abrasion, or blunt force.
Many seeds will remain dormant for dozens of years without some form of scarification, because the seed coating forms a barrier that is impervious to both water and gasses, hermetically sealing the embryo.
I am using a small three-sided file to penetrate the tough seed coats of these Canna seeds from kihaku-gato (after failing with a hammer and a small knife). These seeds are so hard, that in India, they have been used as shot! After many strokes of the sharp edge of the file, the white endosperm peeks through.
#garden science #scarification #germination