Grow wildflowers from seed with these seeds
of wisdom from an avid gardener.
By Marcia Tatroe
There was a time when my garden was stuffed to the gills with annual and biennial flowers. All I had to do was scatter seeds where I wanted them to grow and a floral extravaganza ensued: amaranth, bachelor’s buttons, bells of Ireland, several types of poppies, calendula, bluebells, forget-me-nots, corn cockles, feverfew, hollyhocks, nigellas, red flax and sweet William.
Most varieties self-sowed thereafter, providing years of color from one packet of seeds. Then, one by one, these stalwarts gradually disappeared. Today, nary a poppy remains. After years of flowers going to seed there must be a seed bank of millions in my soil, but they won’t germinate. How is this possible?
Gardens change over time. Some things like weather and water availability are out of any gardener’s control, but I suspect in my case the two factors most responsible are crowding and a heavy layer of organic mulch. Flowers from meadow and prairie origins need sunlight to germinate, those from desert regions even more so.
As my garden has matured, very little sunlight reaches the ground. Organic mulches that mitigate water loss and encourage a healthy population of soil microorganisms effectively block light from reaching the soil. Furthermore, organic mulches composed of garden trimmings, wood and bark may contain chemical compounds that inhibit seed germination, which explains why these same mulches are so good at suppressing weed growth.
To ensure a “floral extravaganza” from seed in your garden, clear away accumulated mulches and start with bare soil. Organic mulches are great for conserving moisture and suppressing weeds, but they block the sunlight that seeds need to germinate.
The key to producing a flower display from seed is to start with bare soil. This is why vegetable seeds readily germinate for me and flower seeds no longer do. My vegetable garden is stripped after harvest, so that new lettuce, peas, spinach and other seeds have no competition from either water- and moisture-stealing roots, or light obscured by companion plants. If you want to grow flowers from seeds as easily as you grow vegetables, the first consideration is to choose a site with as much sunlight as possible, no less than six to eight hours a day.
[pp_gallery gallery_id=”10617″ width=”180″ height=”180″]Also choose a site that isn’t currently hosting a robust population of persistent weeds, such as bindweed, Canadian thistle or smooth brome, that can easily outcompete wildflowers. Pull up or dig out dock, common mallow, crabgrass, dandelions, salsify and any other unwanted vegetation. Rake the soil, leaving it slightly lumpy (you’re going for muffin rather than cake batter), because an uneven surface is better at catching and trapping seeds. Plant early in spring, choosing a day when snow or rain is forecast.
When broadcasting seeds use care not to sow too thickly to prevent overcrowding. After sowing, rake lightly to cover the seeds with soil. Good germination requires contact between the seed and the soil. For small areas use a board to firmly press seeds into the soil. For larger areas rent a roller like the type used to establish lawn grasses. Spread 1 to 2 inches of seed-free straw over the planted bed to help keep in moisture.
Water often enough to keep the seedbed evenly moist for six weeks or until the seedlings are growing strongly. Cut, rather than pull, any weeds to prevent displacing seeds and seedlings.
If all goes well, by June you should have flowers. To have color all summer choose a mix of cool-season varieties—corn cockles, bachelor’s buttons, Canterbury bells, American basket flower and holy thistle—and warm-season flowers like amaranth, China aster, cosmos, snow-on-the-mountain, four o’clocks and kiss-me-over-the–garden-gate. If you can grow vegetables from seed, flowers should be a piece of cake!
Centennial gardener Marcia Tatroe advocates using drought-tolerant native plants and indigenous materials to create a gardening aesthetic unique to this region.