How to save seeds
Most gardeners who have been growing from seed for many years have experienced the heartbreak of a variety they really love disappearing from seed catalogs or the shelves of their local garden store.
“If there’s a variety that you really like, it’s not an uncommon experience, especially as it gets older, that it gets replaced and it is no longer available for you,” said Laurie McKenzie, Northwest research and education associate at the Organic Seed Alliance. “You will literally never grow it again.”
Unless, of course, you plan ahead. One way to make sure you have your favorite juicy cherry tomatoes or sweet summer squash for years to come is by saving seeds from your crops at the end of your growing season. Saving seeds not only helps preserve your favorite varieties for your personal garden, but also for the sake of global crop biodiversity.
“If you really like [a variety] and you can produce your own seeds of it, then it will never go away,” McKenzie said. “Share it with a seed library, share it with your neighbors. There is a protection to keeping it alive.”
Why you should save seeds
There are many reasons to save seeds beyond the conservation of your favorite crops.
“It’s economical,” said Philip Kauth, director of preservation at the Seed Savers Exchange. “If you learn how to save your seeds, you don’t have to keep buying [your favorite varieties] year after year.”
Saving seeds will also help improve your stock over time.
“If you have a variety that you really like and you save seeds from it, you adapt to produce as well as possible in your location because you’re always saving seeds from the best plants: most rigorous growth, best production, most disease resistant,” McKenzie said.
Saving seeds also helps you to be sure where your seeds come from and how they have been produced.
“You kind of have control of your own food supply this way,” Kauth said. “You know exactly how you grew it you know exactly where it came from, and it’s local.”
Seed saving can also help you build a gardening community if you share your seeds with other gardeners.
“If you have a really great variety that you are growing and you think that it’s the greatest thing ever, share it,” Kauth said. “People get excited about growing really great varieties.”
Which seeds should you save?
There are some limitations on the seeds you can save. Open pollinated varieties, which have been bred to be genetically uniform, are generally preferred for seed saving to hybrid varieties, which have been crossbred to produce certain characteristics. A seed package will usually be labeled as open pollinated, heirloom (which are also all open pollinated) or hybrid. While open pollinated varieties will be “true to type,” meaning the saved seeds will look exactly like their parents, hybrid are likely to produce mixed results.
“You can save seeds from a hybrid variety, but what you’re going to get next year is a mix of all the characteristics of all the parents,” Kauth said. “If you have a yellow watermelon that’s a hybrid and you save seeds from it and grow it next year, you may see red watermelon with pink watermelon mixed in with it.”
McKenzie said that there is a common misconception in the gardening community that you cannot save hybrid seeds. While that is not true for “nine out of ten” hybrid varieties, she clarified, you are not able to save seeds from certain hybrids.
“The only hybrids you can’t save seeds from are like a seedless watermelon or one of those brassicas with a cell-mediated fertility issue,” she said.
Is it illegal to save seeds?
Though you are unlikely to run into trouble with the law when you start saving seeds, it is, in fact, illegal to save certain seeds: specifically, those that are protected by utility patents.
“As you get into larger scale, I think you run into it more,” McKenzie said. “Soybeans, corn, sugar beets and alfalfa are hugely utility patent protected. Those crops usually have a genetic modification trait, so it’s usually because [a big company] put a lot of time and money into their research and development.”
Though McKenzie said that such patents are getting more common, small-scale gardeners are unlikely to run into problems with utility patents.
“Generally, your homesteader or backyard farmer is not likely to run into issues,” McKenzie said. “My general recommendation is don’t worry about it if you’re buying seed out of a seed catalog. You could always ask — if a company is really serious about you not saving seeds, they will probably let you know.”
Should you save seeds from the supermarket?
It is possible to save seeds from fruit and vegetables you purchase from the supermarket.
“I have a tomato in the [Seed Savers Exchange] collection that was purchased by a family at a Safeway grocery store in the 1950s,” Kauth laughed. “They saved seed from it and it became a family heirloom for some time.”
The possibilities do not end at the supermarket produce section, either. McKenize recalled a variety of pepper that was bred from a seed saved from a pepper from a salad bar at a pizzeria.
There are some potential limitations, though, especially with modern developments in agricultural technology.
“A lot of fruit [in the supermarket] is treated,” Kauth said. “There are inhibitors sprayed on them in order to get the seeds not to sprout.”
McKenzie and Kauth both added that the plants you find in a supermarket are more likely to be hybrids, so it might be more challenging to breed the exact variety you are looking for.
“I don’t recommend it, but it can be done,” Kauth said. “If you find something you really like, you can try it, but you could probably find something a little bit better than what you get at the supermarket.”
The method for collecting and saving seeds will depend on the crop you are growing. The types of seed saving can be divided into two main categories: fleshy crops like watermelon, peppers and tomatoes, and dry seeded crops like beans, radishes, lettuce and various brassicas like broccoli.
How to save seeds from fleshy fruits and vegetables
Saving seeds from fleshy crops entails three main steps:
- Scoop seeds out of the pulpy flesh.
- Wash seeds thoroughly to remove plant material.
- Dry the seeds.
Drying the seeds is especially important to prevent moisture build up, which can cause molding. There are different strategies for properly drying damp seeds. Winnowing is one method where you use gravity and the wind to separate seeds from chaff by pouring the seeds from a container into a bucket.
“As it falls, the seed is heavier than the chaff,” McKenzie said. “Ideally it will fall straight down, and if there’s a little bit of wind, it blows that chaff out of the stream of seeds.”
You can also use a method called screening.
“We put all our seeds on window screens with a box fan blowing on them,” Kauth said. “Put it on a low gentle breeze because you don’t want them blowing away. And you don’t want to put them under direct sunlight because that will start breaking down the seeds.”
Many of the materials for cleaning and drying seeds can be found around your house.
“You have a lot of seed cleaning equipment in your kitchen and garage,” McKenzie said. “You can use hardware cloth, colanders or milk crates. You’re just going to have to experiment.”
How to collect dried seeds
Saving seeds from dry crops requires knowing a little bit about your plants — namely, when their seeds are ready to collect.
“The classic crop type for that is beans,” Kauth said. ”As the pods start to mature, they get brown and brittle and crusty. That’s when the seeds are ready to save.”
Broccoli is a slightly trickier example. Besides the fact the broccoli is a cross-pollinating plant and often naturally hybridizes with its close relatives, you will have to sacrifice a head of delicious broccoli because the unopened flower buds, which will turn into the seeds, make up the part of broccoli that we eat. Instead of harvesting, allow the broccoli head with the traits that you want to preserve to mature, turning from green to yellow as the flowers bloom and turn into pods. Hang the plant to dry for about two weeks, remove the pods and crush them (either by hand or gently with a rolling pin) to remove the seeds.
Saving dried seeds doesn’t require the extra steps you have to take when saving seeds from fleshy fruits and vegetables.
“If you’re interested in seed saving, start with something easy,” McKenzie said. “I guarantee in a couple of years, you’ll have all sorts of interesting opportunities.”
That makes beans an easy first-time crop to work with..
“Beans are probably the easiest crop type because you don’t have to worry about really processing the fruit,” Kauth said.
McKenzie added that peas, lettuce and tomatoes are also relatively easy.
“When [lettuce] goes to seed, it will throw up big stalk. The seeds themselves are each attached to a little sort of puff off,” McKenzie said. “Tomatoes are great, and also an easy one to save seeds from. The only thing with tomatoes is that fermenting the seeds is highly recommended.”
Some crops are more challenging to save seeds from, either because the seeds are difficult to find and remove or they take longer to flower.
“Rutabaga, mustard greens, kale — those particular crop types pose their own challenges,” Kauth said. “A lot of crops that we eat are biennials. Carrots, for example, take two seasons to flower. You overwinter crops in order to get them to flower.”
Where to store seeds
Once your seeds are clean and dry, you need to find a place to store them for the next growing season.
“You do want to save your seed clean,” McKenzie said. “The bits and pieces especially if you have any leaf or petal tissue they will retain more moisture than you want in the seed. If they’re warm and wet they start thinking about growing, and you’re creating an environment for mold and decay.”
Seeds should be stored in a cool location. A refrigerator or freezer is best.
“You can store them in your refrigerator,” Kauth said. “If you want to store seeds for long term purposes, I recommend using a freezer.”
You can also store seeds in a cool room or basement as long as the humidity and temperature remain relatively low and stable.
“You want to keep them in a cool and dry place,” McKenzie said. “If you store them in your living room at 65 to 70 degrees, they may start sprouting. Generally for a home gardener, you don’t have to have a root cellar. The north side of your house in a closet is great, or in a room you don’t heat.”
McKenzie said that a good rule of thumb is to keep the sum total of the values of humidity and temperature (in Fahrenheit) below 100.
How to store seeds
No matter what location you choose, there are a number of different containers that can be used to store seeds, though breathable, permeable containers are best.
“You can keep them in lots of different vessels: envelopes, bags, jars and canisters,” McKenzie said. “It’s a safer bet if you store them in a muslin bags or coin envelopes. That way, they can breathe.”
“We use special foil packets to put seeds into, but you can store them in brown paper bags,” Kauth added. “Some people store them in plastic bags. It’s not ideal because seeds like to breathe. Plastic isn’t super permeable.
Can you develop your own strain from saving seeds?
Some people save seeds in order to develop crops that are better adapted to the local environment, like high-altitude gardens. But there is some debate over how long that development will take.
Kauth said it is possible to develop your own strains of a crop if you save seeds year to year, but it takes a lot of time.
“In my opinion, it takes much longer than people think,” Kauth said. “If you can start growing these things every year for five years, you might see some improvement on yield and performance. To get it to fully acclimate to your climate is going to take a lot longer.”
McKenzie disagreed. She said that, especially if there are extreme environmental events that pressure the population, the process of creating your own strain can go even faster.
“It depends on how much selection pressure there is,” she said. “I’ve found it can happen really quickly. In a year or two, you can really see a major difference, but it depends on a lot of things.”
Ultimately, Kauth and McKenzie could both agree on one thing: seed saving is fun.
“It’s very rewarding,” Kauth said. “It’s fun for kids to do. It’s fun to get those varieties that you really love and hold on to them and grow them from year to year.”
“It’s just a really incredible, magical process to be a part of,” McKenzie added. “It’s very engaging to create a relationship with the plants that you’re working with. You kind of start seeing the world in a completely different way.”