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Saving Seeds from Your Garden

September 17, 2020

By Rita Shaw, Volunteer, Royal Botanical Gardens.

There are several reasons for saving seeds from your garden.

  • Using seeds you have collected will save the cost of buying seeds the next year.
  • If you have a vegetable you really enjoy for its flavour, or an annual flower that you really like, then you are guaranteeing that it is available even if it disappears from seed catalogues or is sold out in the stores.
  • Along that same line, saving seeds will ensure that the genetic diversity possessed by a plant will survive even if it is not continued to be sold commercially. This is especially true of heritage plants.
  • You can donate seeds collected to RBG’s new seed library.

RBG’s Seed Library

RBG started a seed library in early 2020, allowing users to “borrow” packages of seeds to take home and grow annuals, perennials and veggies from the gardens of RBG as well as from several donors. These are free with the only request being that some of the seeds produced from the plants grown be donated back to the library.

If you have questions or are ready to donate contact Erin Aults (

RBG seed library drawer filled with envelopes

Hybrid vs. Heirloom (Heritage) Vegetables

A hybrid is a plant that has been developed by breeding two different varieties in order to pass on certain desired characteristics to the new plant. These will often be labelled as either hybrid or F1 (first filial generation) or F2. The seeds collected from these plants will often revert to the characteristics of only one of the originals and so will not be exactly like the plant it was collected from and may not have the flavour or other characteristic expected.

A heirloom is a plant that has had the seeds saved and grown over the years with its characteristics being preserved. These plants are said to be open pollinated, which means that to produce the fruit a plant of one variety is pollinated by another plant of the same variety so that there are no new traits introduced. Some heirloom plants may be self-pollinated, meaning that the flowers are pollinated within the same flower or by other flowers on the same plant.

Seed libraries usually restrict their vegetable seeds to heirloom varieties so that the plants grown will be true to type.

The Basics of Seed Collecting

There are two major categories of mature seeds that determine how and when collection is done.

“Wet Seeds”

Vegetables such as cucumbers, squash, okra, eggplants and tomatoes contain seeds within the fleshy edible fruit. These are usually eaten before the seeds inside are mature. In this case when harvesting the fruits for eating a few must be left on the plant for a further period of time to allow maturation of the seeds to occur. Tomatoes are an exception to this. Seeds are mature when the tomato is ready to eat. Peppers should be fully ripened to their final deep colour and maybe become a bit wrinkly.

The seeds must be washed of any pulp and the seeds spread out to air dry for one or two weeks. Some vegetables such as tomatoes and cucumbers are left to soak until fermented (two to four days) in order to remove the gel coat from the seed.

“Dry Seeds”

These are vegetable such as beans, grains, lettuce and herbs as well as most plants from the flower garden. For these, the seeds are collected once they are dry and hard. In some cases, such as beans and peas, the plants are grown beyond the eating stage until the pod becomes brown and dry. Plants such as lettuce and herbs must be allowed to flower (“bolt”) and the seeds collected when they are mature. Collection methods can vary depending on the structure of the seed head, but often it is a matter of bending the spent flower into a paper bag and shaking out the seeds. The seeds can be separated from flower remnants (chaff) by using a kitchen sieve.

Bean pod halved with dried beans inside

Storing Seeds

Once dried, seeds should be stored in paper envelopes labelled with name, date of harvesting and any other useful information. Place the packages in a sealed container and store it in a cool dry place such as a basement area. Seeds will dry out in the fridge and can go moldy in plastic bags.

Some seeds require certain conditions for germination to occur, or to speed up germination. This is true mainly for perennial plants. For instance, Pawpaw seeds should be stored moist and cold over the winter. Seeds from the RBG seed library come with instructions. If collecting seeds from your own plants look up the information online.

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