Introduction to Seed Saving
Seed saving can seem daunting at first, but after learning a few of the basics, you'll be on your way! Read the introduction below, and then check out some books, videos and websites to learn more.
In order to save quality seeds from your plants, you need to understand how each one reproduces.
Luckily, botanists have organized plants into families, based on similarities in their reproductive structures (flowers). This means that all the plants in one family have reproductive structures that function in the same way and, therefore, have very similar seed saving requirements!
Each family is further divided into genera (singular: genus). Plants within the same genus are closely related.
Within genera are individual plant species. Plants of the same species can breed to produce offspring just like themselves.
Cultivars and varieties are variations of the same species. They can readily cross with other cultivars of the same species, but cannot cross with cultivars of other species.
When we save seeds, we're usually trying to preserve a cultivar or variety so that it grows ‘true-to–type,’ meaning that the seeds grow into plants which share the same characteristics as their parents.
Cultivars and varieties of this species: zucchinis, pumpkins, acorn squash, ornamental gourds
Zucchinis, pumpkins, acorn squash and ornamental gourds are all cultivars of the same species, Cucurbita pepo. They've been selectively bred over centuries for their various characteristics and will readily cross with each other if not isolated or hand pollinated. They are like breeds of dogs, also all descended from a common ancestor species, Canis lupus familiaris. If you leave your golden retrievers and your German shepherds out in the garden together, they will breed to produce mutts. The same goes for your zucchinis and your pumpkins!
Types of seeds
Only open-pollinated and heirloom seeds should be used for seed saving. These plants have been bred and cultivated naturally for generations so their characteristics are stable. When seed growers produce open-pollinated seed, they isolate varieties of each species from other varieties of the same species. Plants of each variety are only allowed to pollinate others of the same variety. This results in a robust mix of genes in the seeds while keeping their distinguishing characteristics stable. If different varieties of the same species are allowed to openly pollinate each other without isolation, the resulting seeds will inherit a mix of characteristics from those different varieties. In other words, they will not be true-to-type. Hybrid seeds cannot be used for seed saving as they have been bred from two inbred parent strains. Seeds saved from these plants will grow into offspring that are different from their parents, or not grow at all! These seeds are marked 'Hybrid', 'F1', or 'Filial 1' on the packet. Seeds marked PVP, or Plant Variety Protected on the packet should not be used for seed saving as the reproductive rights for those seeds are owned by the breeder who developed them. Similarly, GM or Genetically Modified seeds should not be used for seed saving. These seeds have had their genes manipulated and are proprietary to the company who created them.
Types of reproduction
Self-pollinating plants have 'perfect' flowers that contain both male and female parts. Fertilization occurs within the flower. These plants are much less likely to cross-pollinate with other plants because their pollen does not need to travel by wind or insect.
Out-crossing plants have separate male and female flowers on each plant, or have completely separate male and female plants. It is more difficult to save seeds from these types of plants because they are more likely to cross with other cultivars of the same species. They rely on wind or insects to move their pollen from flower to flower. Their pollen can sometimes travel surprisingly long distances!
For the most part, plants in these families are self-pollinating. They do not cross easily, even within the same species.
Moderately easy-to-save seeds
These plants are out-crossing, they will cross with other plants of the same species. Some of these plants are also biennial, meaning that they flower and produce seed only in the second year. In order to save seeds from biennial plants, they will need to be over-wintered.
These plants are out-crossing and can spread their pollen over long distances. They may require special techniques like hand-pollination to ensure they don't cross with other varieties.
Six tips for saving seed from Seed Matters