July 19, 2023

Scarification - noun

Definition: A seed pretreatment technique used to weaken the seed coat and allow the seed to start imbibing water and induce germination.

Scarification in the Forest Garden:

Many seeds have hard seed coats that allow them to stay dormant until conditions become ideal for growth. 

Forest Gardeners scarify species with hard seed coats to ensure faster and more uniform germination. Otherwise, those seeds can lay dormant for long periods of time. If a Forest Gardener is filling their nursery bed with a species that has hard seed coats, planting the seed without pretreating them would lead to sporadic germination, making it more difficult and time consuming to tend them. To avoid this, Forest Gardners can scarify their seed using one of two techniques. 

The first scarification technique is used when working with a smaller quantity of seeds. It involves using either a sharp knife or sandpaper to nick the hard seed coat and allow water to penetrate more easily once sown. This technique requires precision and controlled force to avoid breaking the seed or damaging its radicle. 

The second scarification technique can be used with larger seed quantities as nicking the seed coats of hundreds or thousands of seeds is time-consuming and labor intensive. As an alternative, many seeds are able to benefit from a lengthy soak in water. This can vary from 6 hours to 12 hours or even a full day. By soaking the seed for an extended period, the seed coat will soften and allow for water to penetrate more easily, artificially inducing germination. Forest Gardeners must be attentive to the species they are soaking as the rigidity of the seed will determine how long the seed should be soaked in water and at what temperature. 

Join our FGTC Facebook Group to get connected with a global community of agroforesters.