Saving water with low-water ornamentals is a perfect xeriscaping strategy. You also can save money on low-water annuals when planning next year’s garden by collecting seeds from spent flowers and wildflowers. Think of the possibilities. For example, that wild daisy that pops up between your fence and alley every year would look really pretty in the new rock garden in your front yard. Fall is the time to gather seeds from flowers you’d like to have in next year’s garden.
When to collect flower seeds
Select a healthy plant, free of insects. If you normally deadhead the blooms regularly, leave a few to go to seed. That’s also true, of course, if you want to see more of a particular flower in the same general area of your garden or lawn next year. If you completely deadhead or shear off all of the spent blooms, you have less chance of local reseeding. It’s just too bad that we can’t control where the wind blows or other elements.
Make sure the seed head is fully mature. The seeds should be dry, usually brown. They’ll likely fall off the flower head when shaken slightly. So be ready to catch them with your hand, an envelope, pantyhose or a paper bag. It really doesn’t matter, as long as you can catch them, keep them dry and prevent them from blowing away. Then, either mark down or remember the plant from which you gathered the seeds.
There’s a chance that you can wait too long to gather seeds, but it depends on the plant, weather conditions (such as wind and humidity) and local birds. The plant could go dormant before you gather seeds, or the seeds could dry and all drop or blow away, so it’s a good idea to check the flower often as it begins to mature.
How to store seeds
Keep collected or purchased seeds in a cool, dry and dark place. Paper bags protect the seeds, but allow some air circulation to prevent mold (unless you take the step of drying seeds mentioned below). A constantly cool temperature and low humidity will help keep seeds fresh for at least a year. Storing them longer requires more steps, such as drying them at 100 degrees F for six hours. You can do this in a microwave oven if you can control the temperature, or outside in a warm climate, preferably keeping the seeds in the shade.
Once dry, seeds should be stored in sealed cans or jars, which are preferred to plastic bags. The sealing prevents oxygen and moisture from entering the containers; those are two factors that promote germination. Although the optimum temperature is below 50 degrees F, you shouldn’t freeze seeds.
A few cautions
You can’t collect seeds on public land, and should not take seeds from any rare or endangered flower. Designated organizations take care of that. If you want to gather seeds on private land, even if it’s not in use, you should get permission from the land’s owner. Otherwise, it’s fairly simple gathering seeds from flowers and grasses. I’ll address vegetable seed gathering next week.
If you don’t have space in your refrigerator or a similar cool, dry spot for storing the seeds you gather, try exchanging seeds for space with a friend. Or buy seeds each year for common flowers. Truly, seeds are relatively inexpensive compared with plants and you will soon learn which flowers do best in your zone and landscape. In my opinion, unless you have optimum collection and storage conditions, you’ll have lower germination rates with gathered seeds than with those you buy. Still, we continue to gather and broadcast seeds around our place and let nature take it from there, or store some for next spring. And I applaud all efforts to gather and reseed, especially for native wildflowers that use little to no water!