This treatment of seeds before stratification removes the flesh and skin which maintain dormancy and inhibit germination. Experience has shown that the process increases the germination rate of hawthorn, holly and rowan. Although it is a bit of extra work, it is recommended to maximise your return on collecting berries but it is not essential: most berry seeds will germinate after stratification with or without preliminary maceration.
- First obtain a strong watertight container. A strong, flat bottomed bucket is usually adequate. Next you need a pulverising tool, e.g. a large potato masher or a rounded 1.5m pole.
- It is easier if the berries are fully ripe as crushing them can be difficult otherwise.
- Half fill the bucket with berries and add a litre of water. The addition of the water will reduce the tendency for the mixture to stick to the masher.
- An up and down gentle pounding action with the pole or masher will reduce the berries to mush.
- The resulting mass of pulp, skin and exposed seed may then be stratified in the usual way or the seeds may be separated out.
Note: using a rounded pole about 1.5m long saves having to bend over the container and the weight of the pole helps with the pulverising.