Vegetable Seed Saving: What You Need to Know

To minimize the chance of cross-pollination, keep a handful of bean or pepper plants out of the reach of bees and other pollinators. I use a portable cold frame with pull-over netting.

Another option with all self-pollinating varieties – particularly with beans and peas – is to cover the plants with lightweight tulle netting. Drape it over your plants before the flowers open. You can also assist the pollination process by gently shaking the plants a couple of times a day to allow the pollen within the flower to reach the stigma, but it’s not absolutely necessary. Once fruit begins to set, remove the netting.

To save pepper seeds, allow the best-looking peppers to fully ripen. Pick the pepper, cut out the seeds and allow to dry completely on a paper towel or screen.

For beans and peas, leave the pods to dry completely as long as the weather permits. This is usually six weeks past when you would harvest them to eat. If a frost threatens, pull the entire plant up by the root and hang it upside down in a garage or storage shed to dry. To collect the seeds, pop open the pods and spread the seeds on a towel for a week to ensure they’re completely dry before storing them. 

When saving seed from lettuce, bolting is a good thing. Each tiny white or yellow blossom will produce a single seed. After the lettuce has gone to seed, allow it to ripen a couple of weeks before harvesting. Shake the cluster to gather ripe seeds or cut the stalk and hang it upside down over paper to collect fallen seeds.

Imperfect but delightful

Other fruits and vegetables are more challenging because they don’t have perfect flowers; they have separate male and female flowers, which require insects or wind for pollination. This makes segregation imperative if you’re going to maintain pure strains.

Squash, pumpkins and cucumbers fall into this category. To make certain the offspring are true to the parent plant, any time during the season, cover several female flowers with a brown bag or tulle netting secured at the base to prevent bees from pollinating them. 

The female flowers are easy to find – they have a swollen ovary (looks like a small squash or cucumber) at the base of the bloom, while the male flowers do not. Because you’re keeping the natural pollinators away, you need to hand-pollinate them. To do this, use a small, soft-bristled paintbrush to collect pollen (swirl the brush around the central, pollen-producing stamens) from the male flowers and deliver it to a female flower’s stigma (centrally located pollen-receiving structure) on the same plant. Mark the female flowers you segregated so you’ll know which fruit to harvest for next year’s seeds.