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© yossarianc, some rights reserved (CC-BY-NC) · iNaturalist
Overview
Sidalcea virgata is a herbaceous perennial reaching 12-30 inches (30-75 cm) tall and 12-18 inches (30-45 cm) wide, forming a low, often spreading clump from short rhizomes. Basal leaves are rounded with shallow palmate lobes 1.5-3 inches (4-7.5 cm) across, on long petioles. Stem leaves become progressively more deeply divided toward the upper stem, with the uppermost leaves cut into 5-7 narrow linear segments. Pink to lavender-pink five-petaled flowers 1-1.5 inches (2.5-4 cm) across open in loose, branched racemes from May through July, with peak bloom in June. Each flower lasts 2-3 days; bloom on a single plant extends over 4-6 weeks. Stems are slender, hairy, and often somewhat lax, leaning outward at peak bloom. Hairy schizocarp fruits split into 5-7 mericarps, ripening July through August. Foliage dies back to the rhizome after fall frosts in zones 6-9. Self-seeds in disturbed soil, producing 5-15 seedlings annually around established clumps. Lifespan 5-10 years. Restricted in the wild to remnant Willamette Valley wet prairies and listed as endangered in Washington and as sensitive in Oregon under state conservation rankings.
Native Range
Native to wet prairies, oak savanna openings, and seasonally moist meadows of the Willamette Valley of western Oregon and southwestern Washington, with disjunct populations in southwestern Washington's Puget lowlands. Found in heavy, seasonally moist soils at elevations of 100-700 feet (30-200 m); fewer than 30 documented occurrences remain in Washington.Suggested Uses
Used in Willamette Valley prairie restorations, oak savanna gardens, and pollinator borders in the Pacific Northwest. Spaced 12-18 inches (30-45 cm) apart in groupings of 5-9 plants. Functions as a host plant for larvae of the West Coast lady butterfly and as a pollen source for several Sidalcea-specialist native bees.How to Identify
Appearance
Size & Dimensions
Height1' - 2'6"
Width/Spread1' - 1'6"
Reaches mature size in approximately 3 years
Bloom Information
Flowers from May through July in zones 6-9, with peak bloom in June. Cool, wet springs delay bloom by 1-2 weeks; dry summers shorten the flowering period. Each individual flower lasts 2-3 days; total bloom on a single plant lasts 4-6 weeks.Detailed Descriptions
Flower Description
pink to lavender-pinkFoliage Description
medium greenGrowing Conditions
Sun Requirements
Requires 6-10 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Plant container-grown stock or sow seed in fall in heavy, seasonally moist soils with full sun to light shade. Water during the first growing season; mature plants tolerate summer drought once roots reach the moisture-retaining clay subsoil. Rich garden soils with summer irrigation produce floppy stems that lodge after rain; lean prairie soils produce more upright growth. Powdery mildew and rust fungi affect lower foliage in humid conditions; affected leaves can be removed at the crown. The species is regulated as endangered in Washington under state law, and nursery-propagated stock from regional seed sources is the typical horticultural source rather than wild collection. Crowns benefit from division every 4-5 years in early spring.Pruning
Cut spent flower stalks to the basal foliage in midsummer to limit self-seeding and reduce mildew. Remove dead stems and leaves in late fall after foliage has died back. Divide crowns every 4-5 years in early spring as new growth begins.Pruning Schedule
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