While we haven’t had a hard freeze yet, the lack of warm sunshine is telling my plants that the season is about over. Poppy seedheads act like salt shakers—just invert and shake out the seeds. We missed harvesting some pole beans and they’re now overripe, the pods puffy and enlarged. I’m letting them dry on the vine.
I let some of the cilantro mature and bloom, as the flowers attract lacewings and other beneficial insects. Parsley is a biennial, and I overwintered last year’s crop; it also bloomed this summer. Both are producing more seeds than I will ever use.
I also have onion, kale, and bok choy seeds, plus those from an assortment of flowers. I want to get them out of the garden before they drop and become next season’s “plants in the wrong place,” aka weeds. (If time or weather makes you wait, try bagging the seedhead before the seeds drop, as shown here on some lettuce plants.)
I’m not compulsive about saving my seeds from year to year, but if the plants are going to offer a free sampling, I’m not letting it go to waste, either. There are definite advantages to harvesting our seed crop.
For one, they’re free. As the price per packet has gone up in recent years, I’m happy to spend my gardening budget on other things (like some of those gorgeous neon coneflowers I saw the other day).
If you repeatedly save your own seeds, you can slowly develop your own strain of plants perfectly suited to your exact growing conditions. It helps if you pay attention—you want the seeds from the best plants, those that bolted last, had exceptional flavor, or were slightly more frost tolerant, for example.
You know your seeds are the freshest possible, that they were stored correctly (we’ll come to that in a moment), and that they were grown to your standards. And then, there’s that sense of satisfaction about “growing your own” no matter what it is. Isn’t that why we grow our own veggies in the first place?
If you want to save seeds, there are a few things to know. I alluded to parsley being a biennial. So are carrots, beets & chard, celery, endive, leeks & onions, salsify, and anything in the cabbage family: Brussels sprouts, cabbage, cauliflower, collard greens, kale, kohlrabi, rutabaga, and turnip. All of these bloom in the second growing season after planting, then die. If you want to get seeds, you have to overwinter them. And while all of these are somewhat frost-tolerant, not all will survive a Colorado winter, especially unprotected.
Your best bet is to wait until the foliage dies down in the fall, then er the plants with several feet of insulation—leaves, straw, whatever you have on hand. I’ve been very successful holding carrots in the ground this way, and those I miss harvesting always put up a flower stalk in the spring.
It’s also critical to know if your plants are hybrids or not. If you remember your high school biology, crossing hybrids doesn’t necessarily result in the traits you are hoping for.
For example, perhaps a breeder has a lettuce plant with good bolt resistance, but it doesn’t taste very good. Another lettuce plant tastes great, but it flowers only a few weeks after being planted. A hybrid might have the good points of both parents. But the hybrid’s offspring may be bad tasting, prone to bolting, or both. If you intend to save seeds from your own garden, look for those labeled “open pollinated” in the rack or catalog.
So now I have a pile of seeds. How should I store them? The most important goal is to keep them cool and dry—according to Oregon State University, 50 degrees and 50% humidity is ideal. This is where Colorado’s low humidity comes in handy. I’ve had good results putting the seeds in zip-lock baggies, squishing all the air out of the bag, then sealing them and storing them in our cool basement. If you live in a more humid area, make use of those desiccant packets that come in everything from aspirin to shoes (you can re-dry them in a barely warm oven), or use powdered milk or rice to absorb moisture.
Many seeds can be kept for years this way. Iowa State University has a handy chart: Life Expectancy of Vegetable Seeds. If you have seeds from previous years, try a germination test to make sure they’re still viable before depending on them for your year’s crop.
Be sure to identify your seeds—what they are, and when they were harvested. You think you’ll remember now, but many seeds look very much alike. You don’t want to be scratching your head next spring, wondering if you’re planting bok choy or Brussels sprouts! (Some markers can wipe off of plastic, so put a slip of paper inside the bag as insurance.)
Mother Nature saves seeds every year. We can too.
Photos, from top: Poppies, onion seedhead, bagged lettuce seedhead, cilantro seeds, ripening carrot seedhead, covering carrots to overwinter, my seed storage box.