Iris Rocky Mountain Iris Missouriensis is a showy, hardy perennial native to western and central North America. Iris Rocky Mountain seeds can be started indoors 6-8 weeks before last frost or directly outdoors in spring and fall. Also commonly called Western Blue Flag Iris, this popular garden perennial grows from branching rhizomes with fibrous roots forming compact, dense clumps of foliage with tough, upright, but slightly relaxed, sword-like leaves and producing lilac-purple, violet-blue with yellow bases iris flowers. Rocky Mountain Iris blooms from May to June attracting hummingbirds and butterflies.
Iris Rocky Mountain is often found growing in open, grassy meadows, along roadsides, in pastures, and Western Blue Flag Iris makes a welcome addition to wall-side borders, city gardens, flower beds, borders, cottage gardens. It helps germination if the Iris Missouriensis seeds are soaked overnight in warm water before planting to soften the hard seed coat, and the seeds have to be planted not deeper than 1/8 of inch. Rocky Mountain Iris grows best in full sun and moist but well drained soil. Western Blue Flag is popular as a long lasting cut flower.
Height: 12-24 Inches
Bloom Season: Spring
Environment: Sun/Partial Shade
Soil Type: Average/Moist/pH 6.6-7.8
USDA Zones: 3-9
Sow Indoors: Winter/Spring (6-8 weeks before last frost)
Sow Outdoors: Spring/Fall
Seed Depth: 1/8 Inch
Germination Time: 25-45 Days