Harvesting Seeds

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The July/August 2003 issue of This Old House features Randy McManus and his weekend home in Dugspur, West Virginia. The cottage and surrounding gardens are lush with wildflowers — even the sod-covered roof is a riot of colorful hando-sown plants. Here, Randy offers some advice on getting your flowers to bloom reliably, year after year.
Although wildflowers like those in Randy McManus's garden will propagate themselves if left to their own devices, collecting and sowing the seeds by hand ensures a profusion of blossoms.
To harvest seeds, wait until the flowers have faded and the seed pods have matured on the plant. This can take anywhere from several weeks for quick-seeding forget-me-nots to several months for hollyhocks, which flower in June but don't produce seeds until the end of the summer. (If a particularly beautiful bloom catches your eye and you'd like to propagate it, tie a piece of ribbon around its stem — once the petals fall off and the leaves wilt, it can be difficult to pick out the prized plant from the rest.) Just when the plants begin to drop their seeds naturally, pick the pods off and separate the seeds from the fruit; throwing the pods into a paper bag and shaking it is often an easy way to free them up. Then place the seeds on a metal baking pan or uncovered cardboard box and allow them to air-dry until they're brown and crispy. If you want to speed up the drying process, try stacking the trays on the sunny dashboard of your car. "A little old lady taught me that and now I do it all the time," says Randy. "You just have to be careful going around curves." Store dried seeds in coin or stamp envelopes, label them, and stash the packets in a cool, dry place, like the freezer. Most seeds will keep this way for several years.
Seeds can be sown as early as January or February. "Don't bury them too deep," says Randy. "Seeds like to see the sunlight." Simply scratch the surface of the soil with a garden rake, scatter the seeds on top, and water lightly with a hose. A late frost can kill tender seedlings, however, so when sowing be sure to use only half of the lot; that way you'll have backup if you need to reseed.
Flowers From Seed
Here are two dozen wildflowers that thrive in Randy's garden and will do well in most areas of the United States. Sow the seeds in early spring; they'll lie dormant until conditions are right for them to sprout.
Amaranth (Amaranthus spp.)
Baby's breath (Gypsophila elegans)
Bachelor's button (Centaurea cyanus)
Bearded dianthus (Dianthus superbus)
Black-eyed Susan (Rudbeckia hirta)
Brazilian verbena (Verbena bonariensis)
Clarkia (Clarkia amoena and C. elegans)
Cosmos (Cosmos bipinnatus)
California poppy (Eschscholzia californica)
Corn poppies (Papaver spp.)
Flax (Linum lewisii and L. rubrum)
Hollyhock (Alcea rosa)
Indian blanket (Gaillardia pulchella)
Mallow (Lavatera trimestris)
Love-in-the-mist (Nigella sativa)
Lupine (Lupinus spp.)
Plains coreopsis (Coreopsis tinctoria)
Prairie coneflower (Ratibida columnaris)
Purple coneflower (Echinacea purpurea)
Rocket larkspur (Delphinium ajacis)
Silver ghost (Eryngium spp.)
Spider flower (Cleome spp.)
Sweet alyssum (Lobularia maritima)
Tickweed (Coreopsis lanceolata)