In the Garden:
New England
August, 2007
Regional Report

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Black-eyed Susans are easy to propagate from seed you collect when the cones turn grey.

Collecting Flower Seeds

You have to appreciate surprises if you want to collect seeds from your flowers to plant next year. In many cases it's a gamble because you can't always be sure you'll get. But it's the only way to get a lot of seed for free, and it's a ritual that can be rewarding and fun.

Open-Pollinated Plants
Many long-time garden favorites are open pollinated, so the seeds can be collected and planted to grow more of the same. Sort of. Even open-pollinated varieties won't produce plants identical to the parents if they are pollinated by insects because insects create random genetic combinations when they carry pollen from one plant to another.

So if you grow several different open-pollinated varieties of hollyhocks, for example, the seed you save could produce a range of different colors and both single and double flowers. On the other hand, if you grow only one variety and collect seed from it, you can be pretty sure you'll get plants that look the same.

If open-pollinated plants pollinate themselves (self-pollinated) without the help of insects, like some snapdragons, the seeds are more likely to produce plants that look like the parent because there's less mixing of traits.

Plant breeders create hybrid varieties by carefully crossing specific parent varieties, yielding a very precise combination of traits. However, if you plant seed you collect from a hybrid variety, you're likely to get plants that don't look much like either parent. This can be a waste of time, or a good science experiment -- take your pick. Your seedling plants may harken back to a less attractive ancestor, or you might end up with a real show-stopper. Seed packets and plant labels will note if the variety is a hybrid.

Collecting Seed
Here are tips for collecting seed from some flowers that may populate your gardens, or from those that you wish would.

Bachelor's Buttons (annual). The blue color is dominant in these plants so it's harder to get white-flowered plants from collected seed. If you want white, pull out all the blue-flowering plants when the flowers open. Collect the seed heads in a paper bag as soon as the flowers fade.

Black-Eyed Susans (annual). When the cones turn gray, snip them off and rub out the seeds. Sow them in the fall or early spring and they will bloom the first year.

Cosmos (annual). Here again, the dark colors in the mixtures of Cosmos bipinnatus are dominant, but the less popular yellow cosmos will produce true from seed because it's a different genus (C. sulphureus). Collect the seed heads when they turn dry and rub off the seeds.

Delphiniums (perennial). The dark colors will predominate in these mixtures. When the seed capsules begin to open, shake them into a paper bag. The seeds need a cold treatment before germination, so you can either sow them in ground in the fall, or sow them in a seed tray and place it in the refrigerator for two weeks in early spring before setting it under lights or in a sunny window.

Foxgloves (biennial and perennial). If you've tried planting these from seed you collect, you may have noticed that you get mostly the dark purple color. This type is dominant so when two different-colored varieties cross pollinate, the purple coloration often wins out. A long-lived planting will eventually turn mostly purple for this same reason, as plants self sow and older plants die out. When the bottom seed capsules begin to open, collect the seed in a paper bag and dry it before storage.

Hollyhocks (biennial and perennial). You'll have the best luck reproducing double-flowering, open-pollinated varieties. A couple of weeks after the plants have finished flowering, place the seed capsules in a paper bag and let them dry until the seeds fall out. Sometimes you'll need to rub them out.

Marigolds (annual). Double-flowered varieties are dominant so if you prefer singles, buy your seed. Cut off the seed heads when they turn brown and rub off the seeds.

Poppies (annual, biennial, perennial). Single flowers are dominant, as is the red strain of corn poppies or Shirley poppies (Papaver rhoeas). The seed heads are lovely in dried arrangements, and you don't have to destroy them to harvest the seed; just shake them upside down into a paper bag. Sow them this fall directly in the garden or store them over the winter.

Snapdragons (annual). Because these are self-pollinated, you have a better chance of getting plants that look like the parent when you save seed. That is, unless your plants are hybrid varieties. If you have some plants that have self-sowed from the previous year, save seed from these because they have proven to be hardy. The seeds are ripe when the capsules have turned dry and brown. Cut them off and shake out the seeds.

Sunflowers (annual). You'll be in a race with the birds to get to these seeds. They are ready for collecting when the petals have fallen and the stalk behind the head begins shriveling. Cut off the heads, cover them with netting or cheesecloth, and let them dry in a warm place.

Choosing the Best Parent Plants
There's always some variability in a planting of the any variety. Some will have stronger stems, and there will be slight color variations even among plants of the same color. If you plan ahead, you can save seed from the best ones. Choose plants that have the best color and stature, and tie a piece of yarn loosely around the stem when they are in bloom, or set a plant label in the ground next to the stem. In general, avoid saving seed from weak-stemmed plants, but lupines are an exception; the weaker stems often produce the best colors.

Storing Seed
Be sure to remove any chaff that may surround the seeds because it can hold moisture and turn moldy later on, killing the seeds. If the seed is tiny, you can use a colander to separate it from the chaff. Otherwise try a shallow bowl or pan so the heavier seed can fall to the bottom and you can scoop the chaff off the top.

Store seeds in a tightly sealed container to keep out moisture, such as a glass jar (baby food jars are handy) or a film canister. Keep them in a cool place -- in the refrigerator if there's room. You can store several different types of seeds in separate, labeled envelopes in the same jar.


Special Report - Garden to Table