At the end of the growing season, you may be thinking about saving seed from a particular plant from your garden that you can sow next year. Saving seed is not difficult to do but some care must be taken to insure the viability of the seed to reproduce the following season. Keep in mind that the seed produced by many hybrid plants may not produce the same variety of plant as the parent plant.
First, a couple seed definitions. Seeds fall into two groups–orthodox and recalcitrant. The names refer to the response of seeds to long-term storage in dry conditions at subzero temperatures.
Orthodox seeds are dry, usually small, and comprise the great majority of seeds. They are responsive to their surroundings and can deteriorate rapidly when stressed. They also are able to survive intense desiccation and can survive decades, sometimes centuries under favorable conditions.
Recalcitrant seeds are moist and usually large (most nuts, acorns, etc.). They remain alive only while moist.
We will concentrate the discussion on dry or orthodox seed collecting.
There are three principles to collecting and cleaning dry fruits.
- Collect only when ripe, usually indicated by the appearance of the fruits. Dry fruits change from green to yellow as they desiccate. As they mature they will turn straw-colored or brown. There can be exceptions to this rule. Some members of the Buttercup family are collected in an immature state as they produce seedlings more readily. Hellebores release seeds before they are completely dry.
- Collect only in fine weather when plants are dry. Wet seeds are more prone to mold. If this is unavoidable, seeds should be immediately dried by spreading on sheets of paper towel and on a radiator or dry, airy room with low level heat for several days. Don’t put in a hot oven to dry!
- Try to collect seeds, not unwanted material such as pieces of the plant, soil, sand, or dead leaves. If debris is sown with the seeds, it can provide sites for infection by pathogenic fungi.
Orthodox seeds should be kept in dry, well ventilated conditions until they lose surplus moisture.
Suitable post-harvest containers can be:
- Unglazed brown manila paper bags. Make sure the corners are sealed. You can place the cut ends of spikes and capsules in the bag while they are drying, leading to the release of seeds into the bag.
- Seed trays can be lined with paper to hold bulkier collections.
- Plastic pots with paper or polystyrene cups. These are convenient for small quanties. Be careful to secure to avoid spilling.
- Plastic bags only for succulent fruits–not for seeds from capsules and other dry fruit.
NOTE: Sealed containers do not allow the escape of water vapor and can create conditions for mold growth.
Numerous plants (geraniums, some members of the pea family, violas, acanthus, streptocarpus, and impatien) distribute their seeds ballistically. They have structures that spring open and hurl their seeds. They should be stored in a closed bag to prevent the ripe seed from being scattered.
Preparing the seed for storage will be covered and an article to follow soon.