Seed Saving Savvy

In an earlier Q and A session, Cathy Christie (Master Gardener in training and Chair of the Kingston Area Seed System Initiative (KASSI)) introduced us to the concept of seed saving, some seed terminology and examples of seeds to save.  She also shared information about KASSI. If you are learning about this for the first time or want to refresh your memory, read my earlier blog:  Planning a Seed Saving Garden.

This blog starts with a brief seed saving primer from Seed Savers Exchange, some recommended references and then your questions grouped as follows:

  • Seed saving principles: temperature to store seeds, ways to pry open seed pods, planting distance to ensure no cross pollination and seed saving for perennials.
  • Specific vegetable crops including the Brassica family, Cucurbita species and carrots
  • Specific flowers including hollyhocks,  morning glories, allium and lupin.

The blog ends with some recommended local sources for open-pollinated seeds.

Seed saving primer

When saving seeds, the Seed Savers Exchange publishes a SEED SAVING GUIDE which highlights all the relevant factors to consider when saving seeds. Below is one example – the tomato.

SpeciesSolanum lycopersicum
Life Cycleannual
Primary Pollination Methodself or insect
Recommended Isolation Distance for Seed Saving10–50 feet (3–15 m)
Population Size (Number of plants)1
Viable Seeds5–10
Variety Maintenance20+
Genetic Preservationtomato

Recommended References

Seed Savers Exchange :  A nonprofit organization based in Decorah, Iowa which focuses on promoting and encouraging the tradition of saving and sharing seeds. Its website is a great source for information to support successful seed saving. Some of the topics covered include Garden Planning/Tips, Seed Starting, Plant Care, Pollinators, Soil, Seed Saving and Crop-by Crop Growing Guides.

The Seed Garden – The Art and Practice of Seed Saving by Lee Buttala and Shanyn Siegel.

This book provides straightforward instructions on how to collect and save seeds from your favorite heirloom and open-pollinated plants.

Questions and Answers

I Seed saving principles

What’s the best temperature to store seeds? Do they need to be refrigerated?

Seeds should be stored in a cool, dry place. They will begin to germinate in humid conditions. Seeds should only be refrigerated if they require a vernalization period.

The Gardening Know How website describes “ Vernalisation is a process of going dormant in cold temperatures, which helps certain plants prepare for the following year. Plants that have vernalization requirements must be exposed to a certain number of days of cold temperatures below a certain threshold. The required temperatures and lengths of chilling depend on the plant species and variety… After vernalization, these plants are capable of flowering.” Without “enough chilling time, these plants will produce a poor crop or, in some cases, they will not flower or produce fruit at all.”

Fun fact: the root always comes out first when a seed begins to germinate.

Can you share some tips/tricks on how to pry open, for example, dried daikon seed pods – the seeds are tiny!

Create your own thresher. You can place the seeds into a feed sack or sheet, put on heavy boots and stomp on them. A rolling pin will also work. Seed Savers Exchange has more information, including how to work with seeds from the Brassica family.

To save open-pollinated seeds do you have to grow them away from other varieties of the same plant? And how far?

Quick recap: KASSI’s website described three categories of seed; Open-pollinated, Hybrids and patented seeds. Open-pollinated plants grow like their parents. Pollen flows openly (freely) between the plants. They retain their genetic diversity and produce plants that adapt to changing growing conditions. They produce seeds that can be legally grown, saved and shared.

Saving open-pollinated seeds depends on how plants are pollinated. There are a number of ways to avoid potential cross pollination.

For vegetables like tomatoes, beans, lettuce and squash, the “easy savers”, grow each variety at least 10 to 20 feet apart from other varieties. You need only one tomato, bean and/or lettuce plant to save seed; however, more are recommended to ensure crop resilience.

For lettuce, you can grow a number of varieties together and manage pollination by allowing only one plant to go to seed.

If you are unable to maintain distances, use a blossom bag. A wedding favor bag can serve this purpose or you can make your own. You place the bag over the flower of a self-pollinator such as a tomato, preventing other pollen from entering the flower.

I never noticed if perennials mention “open-pollinated”?

Many perennials are grown from cuttings or suckers. Collecting seed is a good way to acquire native plants.  It’s important, however, to identify your plant accurately before you start.  Don’t forget to ask permission if you are collecting from someone else’s property. Also do some research about collecting rare native plants, as there may be restrictions. Another aspect to consider is how much of the available seed you remove. A recommended guideline from the North American Native Plant Society is 10% of the total to maintain the plant colony. This means you need to consider whether someone else has been collecting in the same area. Don’t forget, to ensure seedlings are true to the parent, you need to respect isolation distances required to avoid cross pollination.

Were you able to hold a Seedy Saturday last March, or did you have to cancel because of the pandemic?

Unfortunately, it was not possible this year because of the pandemic. The small group of KASSI volunteers has decided to focus on “grow outs” instead, to produce more seed for next year. Last year, about 15 varieties of seed were grown out. This year there are 50. While KASSI seed is not readily available, if you are interested, contact Cathy at

All KASSI seeds are open-pollinated, but there is a story and a good reason for growing each. Here are some:

The Centennial Rocket tomato was bred in Alberta for a short growing season and is ready to eat in some Kingston gardens.

Cucumbers from seed are also currently being harvested as well as yellow and green beans.

All legumes are selected for their ability to be dried (food security and sovereignty) however, most of the beans and certainly the peas, can be eaten fresh.

Local sources of open-pollinated seeds


Bear Root Gardens – Verona

Kitchen Table Seed House – Wolfe Island

These seed companies also have catalogues with helpful information.

II Vegetables

What do you recommend for different plants from the same species like zucchini and pumpkin?

sliced pumpkin on brown wooden surface

Cathy noted that zucchini tends to cross pollinate easily with related Cucurbita species. So, when planting zucchini, plant them far from all other squash. She has three different species growing in her garden: Sibley (Cucurbita maxima), Butternut (Cucurbita moschata) and Early Yellow Crookneck (Cucurbita pepo).

To save seeds that are true to type, each variety must be  800 feet- 1/2 mile away from all other varieties of the Cucurbita species that you are growing. For more information on growing squash, go to KASSI

For more information about specific crops, go to Seed Savers Exchange. For squash, it covers: how to grow squash, time of planting, spacing requirements, time to germination, special considerations (hand pollination recommended), common pests and diseases, when and how to harvest, eating, storing, how to save squash seeds, life cycle, recommended isolation distance, recommended population sizes, assessing seed maturity, harvesting, cleaning and processing and storage and viability.

The Brassica family is tricky because they all look different.

green vegetables

Cathy has kale in her garden, but no other Brassicas, so she was able to save seeds last year. Because Brassicas are biennial, seed saving from them is more challenging. If you want to harvest Brassica seed, it is best to grow only one type. Alternatively, you can time flowering. For example, KASSI has two different kinds of leeks that are biennial. They are grown beside each other, but each is harvested every other year. As mentioned earlier, blossom bags can also be used. If you are working in an area with limited space, hand pollination is another way to ensure a viable seed harvest.

Seed Savers Exchange described hand pollination as follows: “Hand-pollination is a technique used by seed savers to ensure that plants produce seed that is true-to-type and that flowers are not contaminated by the pollen from another variety. The process varies among species, but with plants that produce unisexual flowers like corn, the uncontaminated pollen from male flowers is transported to the unpollinated stigma of female flowers. Once the pollen is transferred, the female blossom is again covered to prevent contamination by any other pollen”.

What is the best way to manage carrot seed?

white flower with bee on top

The flowers of carrots that have been left to seed should be handled carefully. They are in the same family as parsnip and can cause skin to itch. It’s best to wear gloves, place the seeds in a paper bag, then crush to loosen the seed from the flower. You can also use anold pillow case and a rolling pin. For more information, go to Seed Savers Exchange.

Carrots are pollinated by wind and easily pollinate with Queen Anne’s lace. As Queen Anne’s lace is prolific in our area, don’t be disappointed if some of your seeds don’t grow true. To prevent cross pollination, build a barrier using a row cover or mesh bags.

III Flowers

When allium and lupin drop seed, will these turn into new plants?

blue and pink flower field

Yes. Joyce has many alliums in her wild scape garden. She sprinkles the seedpods in the fall, and they sprout in the spring. Because they are left outside, there is no need for artificial verbalization. The same can be done with lupins.

How long are morning glory seeds viable?

Nancy, one of our Master Gardener’s, has grown morning glory seeds after 5 years in an envelope in her seed drawer. While she is uncertain how long they last she’d caution on the cultivar. She has an old variety that returns year after year. Newer cultivars don’t perform the same way.

I have rust on hollyhocks, and I am unsure of the best way to treat them. I heard you should not save seed as the next generation will be affected. Can you advise on both?

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Happy gardening!

Reporting by Colette McKinnon, Master Gardener in Training,
Rideau 1000 Island Master Gardeners