The Iowa Gardener: Save those seeds

As summer wanes and many of our favorite garden plants set seed, now is the perfect time to practice the age-old art of saving seeds.

Saving seeds is fun, easy, and lets you keep growing your favorite plants from year to year. It also can save you a bundle since seed costs have skyrocketed in recent years.

Which seeds to save?

Many, but not all, plants are suitable for seed saving. There are two main categories for home gardeners to consider: open-pollinated and hybrids.

Open-pollinated seeds, which reproduce naturally through pollination by wind, insects, or other natural means, are ideal for saving because they will reproduce “true” from seed, that is, the seeds you plant from them will look like the parents. Most plants and seeds labeled as “heirloom” seeds are open-pollinated.

Hybrid seeds, on the other hand, result from controlled cross-pollination of two different parent plants and are not suitable for saving as offspring may not be identical to the parent plant. Those tall, strong, gorgeous red zinnias, for example, may come out a disappointingly weak plants with flowers that are merely an off-pink.

Harvesting the seeds

Seed saving starts with proper harvesting. Choose from the biggest, the brightest, the best and the healthiest. Collect seeds from healthy, disease-free plants that exhibit desirable traits such as good flavor, color and resilience. This ensures that subsequent generations of plants will retain these desirable characteristics.

With some plants, the seeds are very simple to harvest since you can spot the seeds developing and drying right on the plant, as with hollyhocks, marigolds, cosmos, zinnia, sunflowers, poppies and more. With these it’s simply a matter of letting the flowers mature on the plant and then collecting them once the flower heads and/or seed are hard, dry, and easy to pull off the plants.

With more fleshy fruits and vegetables, allow the plants to mature fully on the vine before collecting seeds. With plants like beans and peas, that’s easy. Just let them mature, shrivel and dry and then pop the seeds out of the pods.

With plants like pumpkins and squash, let them mature on the plant until they are a bit past their prime for eating but not rotting. Then split open, remove the seeds, and let them dry on paper and cardboard. For wetter plants, like tomatoes, harvest them when they are fully ripe and slightly soft.

Very juicy, fleshy plants, like tomatoes, melons and cucumbers need to first go through a process called wet-fermentation, where you put the pulp and seeds in a jar with water and let it ferment for a few days before removing and drying the seeds. Look online for details.

How to dry the seeds

After processing, allow the seeds to dry for one to three weeks, depending on their size and how dry they were when you harvested them. Spread them out in a dish or on some paper or cardboard in a sheltered, warm, well-ventilated space. If the weather is very humid, you might want to bring them indoors into a more climate-controlled environment to do this.

How to store the seeds

After the seeds are dry, separate them from the chaff, that is, the bits of leaves, pods, and other plants parts.

Then store them in airtight containers, such as jars or resealable plastic bags. I like to put them into small paper envelopes stashed in a resealable bag. Label carefully. Store in a cool, dark, dry place (such as the back of your fridge) until it’s time to plant them.

Don't limit yourself to collecting seed just from your own garden. If you admire annual plants in a friend’s garden, ask if you can collect any developing seeds. Or save the seeds from any wonderful heirloom or open-pollinated produce you purchase at the farmers market.

You may well find yourself purposely purchasing seeds specifically so that you can save them from year to year. Just be sure to purchase heirloom or open-pollinated types so you can be sure they will grow true from the parent plants.

Then share your seeds with others. You’ll likely find you have far more than you can grow yourself, but they’re wonderful for sharing with friends and other gardeners — the gift that keeps on growing.

Veronica Lorson Fowler is co-publisher of the Iowa Gardener website at www.theiowagardener.com.