Spreading eastward from the foothills of the Canadian Rockies, Alberta is Canada's major agricultural region. Vast crop and grazing fields now cover a large part what was once 11 million acres of Alberta's prairie, says the Alberta Prairie Conservation Forum. Their five-year prairie conservation plan includes educating gardeners in the use of the Alberta's native flowers, with plants commercially available at garden centers. They include perennials and annuals for a variety of growing conditions.
Silkweed (Asclepias speciosa), sometimes called showy milkweed, is a perennial of the milkweed family. Standing between one and three feet high and up to 18 inches wide, this sun-loving plant develops deep taproots in the dry, sandy soil that it prefers. The Missouri Botanical Garden advises you to plant silkweed where it will remain.
Silkweed has straight stems with velvety eight-inch oblong leaves. The gray-green foliage makes contrasts pleasingly with the plant's late spring and summer flowers. Star-shaped, they bloom in three-inch globe clusters of pale pink to rosy purple. Large, rough seedpods follow the flowers, making attractive additions to floral arrangements when dried. Plant in full sun and dry, infertile soil. Sandy or gravelly soils are best.
Rocky Mountain Bee Plant
Rocky Mountain bee plant (Cleome serrulata) stands up to five feet high, with a straight leafy stem that branches at its top. From July to September, the ends of its branches bear showy spikes of white, pink or red-violet flowers with six prominent stamens. Flower clusters get longer as the blooming season goes on.
Lower flowers open first, so spikes may have seedpods at their bases simultaneously with blossoms at their upper ends. The flowers' nectar is irresistible to bees, while birds feed on its seeds. Plant this annual, says the Lady Bird Johnson Wildflower Center, in dry, sandy, well-drained soil and sun to partial shade.
Giant Red Indian Paintbrush
While not as large as its name suggests, giant Indian red paintbursh (Castilleja miniata) is an impressive 18-inch to three-foot perennial with straight, leafy stems. Its lance-like green leaves accent the vivid colors of its flower calyxes (outer coverings). The small green flowers are inconspicuous, but calyxes of orange, pink or red create brilliant, uneven spikes of color that give the plant its name. Plants bloom from May to September.
This plant's drawback, says the Lady Bird Johnson Wildflower Center, is that its roots entwine with and feed off the roots of other plants. It can be difficult to grow from seed and doesn't transplant well. Plant the seeds in full sun and moist to wet, well-drained soil.