There are plenty of plants that when left to their natural habit will produce seeds during the season. It’s what most of them have done for centuries.
They flower, go to seed, drop the seed to ensure another generation.
When radishes don’t head up, I just leave them in the garden. They form pretty pink seed pods. I eat some of the young ones, the rest grow, turn color and then will dry brown.
The key to saving seeds is allowing the plant to reach fruition. Just before it’s ready to drop seed, the gardener swoops in to gather the seed.
The radishes are just about ready. Sometimes a couple pods will open and I’ll know it’s time to harvest.
In my garden I left some peas on the vine, they dried, dropped and now have sprouted for a fall crop.
One thing that’s important is that only open pollinated plants will produce seed that’s true, meaning it will produce the same variety.
Hybrid seeds will revert to parent plant that was crossed to create the hybrid plant. Seeds and plants are always labelled if they are hybrid, if they are not, that usually means they are open pollinated.
Besides radish and peas, I’ll save coriander (cilantro that went to seed), dill, tomatoes, lettuce and anything else I find that reaches fruition as long as it’s open pollinated.
Here’s how I save tomato seed-
Squeeze the seeds into a jar of water and stir them once a day for three days. This ferments the seed, removing the gelatinous coating and killing some soil borne diseases.
Then I lay mine on a coffee filter, let them dry and store them in an envelope. That’s put in an airtight jar like a mason jar and stored in a cool dry place.
That’s how I store all my seeds. First in paper envelopes, then in the mason jars in a cool dry place.
These seeds germinate above 90 percent and some horticulturalist theorize change through evolution to suit your micro-climate.
Try saving a little seed it’s fun. I like to give packets away to gardening friends. You’ll be surprised how good the seed is and how much you’ll save when ordering next season.