How to Scarify Seeds

Bird feeding on seeds in winter

Seed Scarification

It may be intimidating when you receive a pack of seeds that instruct you to scarify before planting.  You may not even know what it means.  Scarification is to weaken or open the outer surface of a seed.  It is necessary for some seeds so that they will germinate.  It isn’t very complicated to scarify seeds, but there is some effort involved.

Bird feeding on seeds in winter
A passerine bird on a sunflower in the snow

In nature, seeds with hard outer shells will naturally break down with the weather or with animal assistance.  Seeds dropped from the plants in the fall will go through the cycle of cold and wet weather that prepares the seed for germination.  The outer surface will soften and crack so that the seed is ready in spring for the warm weather to trigger sprouting.  Another way nature prepares seeds is by using birds and other animals.  As a seed passes through an animal, the outer shell is broken down and the seed will eventually sprout wherever it lands.

If it is too late to plant in the fall and let nature take care of the seeds, you may need to intervene and scarify your seeds (or if you live in an area without cold, wet winters).  We sell several seeds that need scarification to aid in germination, such as Wild Blue Indigo, Wild Lupine and Maryland Senna.

How to Scarify Seeds:

Sandpaper for Scarification
Sandpaper for Scarification

There are several ways to artificially scarify seeds. The basic three methods involve physical, thermal, or chemical ways of removing the outer shell.  At Joyful Butterfly, we typically use the sandpaper method (a physical method).  Below are the steps to scarification by sandpaper.  We also have a sample video.

Scarification by Sandpaper:

  1. Collect items needed: Seeds and medium grit sandpaper.
  2. Place seeds between 2 sheets of sandpaper. Tear the paper in half if it is easier for you to handle.
  3. Using a rotating motion, press down and rub the seeds between the paper.
  4. Check to make sure the seed surface is being scratched.
  5. Continue if necessary. If the outer shell is hard, you may be more aggressive than with softer seeds.
  6. Follow the planting instructions. Be ready to plant once the seeds are scarified.