Annual wildflowers live a short, sweet life. They bloom, make seed and die. Fortunately, they return year after year if left to go to seed.
Besides being lovely to look at, annual wildflowers attract pollinators that sip their nectar and/or cart off their pollen, feeding the insects, butterflies and hummingbirds that, in turn, pollinate the plants.
“True wildflower patches will take on a natural, informal appearance in the garden,” says Amy Jo Detweiler, horticulturist for Oregon State University Extension Service. “They will evolve over time and change as the dominant seeds in the mix spread more quickly.”
There’s more to growing wildflowers than just sprinkling them on the ground, sitting back and watching them grow, Amy Jo says.
First, select an appropriate site. Most wildflowers prefer full sun, well-drained soils and open areas free of weeds.
Water the site you chose for several weeks to germinate and bring up any existing weed seeds. Then, remove any weeds by manually pulling, tilling or using a nonselective type of herbicide.
Once the weeds have died and been removed, you are ready to gently loosen the top 2 to 4 inches of the soil.
Amy Jo says tilling tends to bring up too many weed seeds and cause problems later. Depending on your location, you may need to amend the soil with some kind of organic matter or compost to improve nutrient-deficient soils. You may also need to provide drainage.
Commercial wildflower seeds can be successfully planted in spring or fall. Seeding rate is one ounce of seed per 125 square feet or as directed on package. A hand seed spreader is a good tool for broadcasting the seed. The result is more uniform coverage.
For planting in spring, gently water the site for up to a month prior to planting to improve germination after seeding. Seed in mid-April to the beginning of May. Keep the area lightly irrigated while seeds are germinating if it doesn’t rain.
If planting in fall, broadcast the seed in early November so germination does not occur until spring.
Most annuals’ seeds need light to germinate, so do not cover the seeds. Rather, let them sit on the surface of the soil. Make sure you leave the dead plants long enough so they drop all their seed.
Amy Jo has these suggestions for annual wildflowers:
- Black-eyed Susan (Rudbeckia hirta)
- Blue flax (Linum perenne)
- California poppy (Eschscholzia californica)
- Purple coneflower (Echinacea purpurea)
- Foxglove (Digitalis purpurea)
- Godetia (Clarkia amoena)
- Lance-leaf coreopsis (Coreopsis lanceolate)
- Mountain hollyhock (Iliamna rivularis)
- New England aster (Aster novae-angliae)
- Pot marigold (Calendula officinalis)
- Scarlet gilia (Ipomopsis aggregate)
- Sweet William pinks (Dianthus barbatus)
- White meadowfoam (Limnanthes alba)
- Globe gilia (Gilia capitata)
- Large baby blue eyes (Nemophila menziesii var. atomaria)
Information courtesy of Oregon State University Extension Service.