Asclepias speciosa.
Showy Milkweed, which was first recorded near the Canadian River in 1820 by Columbia University botanist John Torrey, is a perennial wildflower native to the western United States It can often be found growing on rocky slopes, in woodland areas, and alongside roads and streams.
Plant grows to about 4 feet tall and produces fragrant, eye-catching flowers that are pale pink to pinkish-purple.
Attracts numerous butterflies and other pollinators, particularly monarch butterflies whose larvae feed exclusively on milkweed. Typically blooms in its second year.
Showy Milkweed
Growth Chart
Hardiness Zones: 3 to 9 Light Requirement: Full sun Soil Type: Chalk, clay, loam, sand Sow Depth: 1/8 inch Plant Spacing: 24 to 36 inches Germination Note: Cold stratification required Stratification Time: 30 days Bloom Time: June through August Growing Tips
Direct sow just beneath the soil's surface in late fall. Germination will occur after the last spring frost. For spring planting, mix the seeds with moist sand and refrigerate for 30 days (cold stratification) before direct sowing.
A Note on Cold Stratification
These seeds require cold, moist stratification. To naturally stratify the seeds, plant outdoors late fall on a weed-free site and allow seeds to overwinter.
To artificially stratify the seeds, place the seeds and a moist medium (such as a damp paper towel, coffee filter, sand, or vermiculite) in a labeled, sealed plastic bag and store in a refrigerator (33-40°F) for the amount of time noted on the growth chart before sowing.