Seed Saving Basics

After a summer full of harvests, your plants offer a gift that keeps on giving.

If you're ready to take gardening full circle, it's time to get into seed saving. Collecting seeds from the strongest plants you've grown this year helps create a more vigorous crop next season because you'll pass on traits that are better suited to your region's growing conditions. Plus, it's super-easy and you won't have to buy seeds next season!

Ready to collect? Here's what to know and how to do it.

1. Learn Which Seeds to Save

Seed saving success comes down to selecting the right kinds of seeds. That doesn't just mean picking out teeny-tiny pips from the strongest plants in your garden, although that helps! The important thing here is to know how the plant reproduces.

Save Seeds from Heirlooms

You want seeds from heirloom plants. These plants pass on all of the genetic info from generation to generation, so the seeds you collect will grow into plants just like the ones you get them from.

Avoid Seeds from Hybrids

What you don't want are seeds from hybrid plants (anything labeled F-1). Because the parent plant is a combination of several varieties, the traits you love about it this year might not pass on to its seedlings. That unpredictable nature typically makes the seeds not worth harvesting.

  • Easy seeds to save: When it comes to fruits and veggies, any self-pollinating produce like tomatoes, peppers, beans, peas, and eggplants are good choices. For ornamentals, try zinnias, marigolds, coneflowers, echinacea, black-eyed Susans, and sunflowers.
  • Challenging seeds to save: Biennial crops—including root veggies like onions, carrots, and beets—need 2 seasons to develop seeds. To collect seeds from these plants, you have to dig them up, protect them over the winter, and then replant them in the spring. If you're up for a challenge, try it!
  • Difficult seeds to save: Most of your vine crops—cucumbers, melons, squash, and pumpkins—will cross-pollinate via insects or wind, so it's hard to keep the seed line pure.

2. Collect and Clean Your Seeds

Seed collecting techniques break down into 2 categories: Dry and wet. You’re not going to harvest seeds from a sunflower the same way you do from a tomato. One rule of thumb on both? Avoid seeds from any plants that are unhealthy or seem diseased.

Dry Seed Collection

Most flowers and legumes (anything in a pod) are harvested as dry seeds in the fall. Here’s what to do.

  • Leave the heads on your flowers until the petals start to shrivel. Keep the pods on your legumes until they’re so dry you can hear the seeds rattle around inside.
  • Once ready, remove and collect the flower heads or gather the pods. If you’re harvesting multiple plants at once, be sure to keep everything separated so you know what is what.
  • Spread the flower heads or pods on a paper towel and place it somewhere cool so they dry for a week.
  • Remove the seeds from the flower heads or pods using your hands or a small knife.
  • Manually pick out the seeds from the rest of the dry material or use a colander to help speed up the process. Place the colander in an empty stock pot or large bowl and then drop all of the dry contents into it. Move it around for a minute or 2, and the seeds should fall below.

Wet Seed Collection

Almost all fruit and veggie seeds are harvested as wet seeds. Here are the steps.

  • Collect the seeds once the fruit is fully mature. You want it overly ripe but not rotten.
  • Separate the seeds from the flesh and rinse them in a strainer. For tomatoes, tomatillos, and kiwis, you should take it a step further and let the seeds soak for 2 to 3 days to get rid of the goo.
  • Lay your seeds on a flat surface covered in wax paper, newspaper, or a tea towel (paper towels can stick to the seeds).
  • Leave the seeds to dry at room temperature. How long will depend on the seeds, but typically they’ll need 3 to 4 days.
  • A snap test can tell you if your seeds are fully dry. Take a seed, and if you can cleanly break it in half, or if it shatters, it’s dry. If it bends, leave the seeds for another day or two, then try again.

3. Store Your Seeds

Now that your seeds are clean and dry, label and store them properly so you have the best chance for success once the next growing season rolls around. Follow these tips for storing seeds to keep yours in good shape.

  • Control moisture. Dampness can cause your seeds to mold or even start sprouting. Store them in an airtight container, like a glass jar, or enclosed in a breathable material, like a paper envelope. (Plastic bags can trap moisture.)
  • Label your container. Include the name, variety, and date you collected the seeds. For flowers, you may want to note the color.
  • Keep them cool. Find a space in your house that is consistently cool, dry, and out of direct sunlight. Some people use the fridge, basement, or a closet on the north side of the house. Consider adding silica gel packets to help.
  • Plant sooner than later. You can save most seeds for around 3 years, but their effectiveness decreases the longer they’re around. Luckily, planting brings new seeds!

4. Exchange Your Seeds

A diverse garden can help reduce pests and increase pollinators. One of the fastest and most fun ways to achieve this is by swapping your seeds with other savers. There are online communities that mail seeds to each other as well as in-person exchanges where enthusiasts offer up rare or unusual varieties not commonly found in catalogs. Trade in your favorites and grow something new!

Saving those magical kernels your plants naturally produce is a great way to benefit from the entire growing cycle. Best of all, because you can choose to take seeds from your strongest plants, their chance for future success is top-notch. So, go ahead and skip buying seeds next year—you’ve already got your own awesome collection!