Sidalcea gigantea
Giant checkerbloom
(c) Matt Berger, some rights reserved (CC BY) · licence
Family: Malvaceae · Type: Herb · Native
Conservation status: CNPS 4.3
Sidalcea gigantea (Giant checkerbloom) is a native California herb in the Malvaceae family, recognized by clearly distinguished by exceptional size.
Giant checkerbloom is a California native perennial herb found in northern Sierra Nevada and northern California Ranges in moist to wet forested slopes, seeps, stream margins, and meadows at elevations of 900 to 1,650 meters. Flowering from July to September, this plant produces pale pink flowers in spike-like racemes 14 to 18 centimeters long, with 10 to 20 widely spaced blooms. Growing with impressive erect stems 1.5 to 2 meters tall, sometimes with a purplish cast and densely covered in bristly hairs, it spreads via rhizomes up to 40 to 60 centimeters long. Its large basal leaves are deeply lobed, with lower leaves reaching 11 to 12 centimeters wide, typically rounded and divided into 4 to 5 segments, covered in stellate (star-shaped) hairs. The fruit consists of 7 to 8 segments approximately 3 millimeters long, with a network-like textured surface and a short beak.
Identification and appearance
Key characters: 8 sympatric species - clearly distinguished by exceptional size
Habitat and range
Habitat: Moist to wet forested slopes, seeps, stream margins, meadows, mid to upper conifer forest
Elevation: (640)900-1650 m
Bloom period
Sidalcea gigantea blooms Jul-Sep.
Conservation status
CNPS 4.3
How to tell it apart
vs Malva: Sidalcea has no bract ring below flowers and anthers in two circles; Malva has 3 bracts and scattered anthers.; vs Clarkia: Sidalcea has mallow flowers with fused stamens; Clarkia has 4 separate petals and 8 separate stamens.; vs Geranium: Sidalcea has bowl-shaped flowers with fused stamens; Geranium has 5 separate petals and long beaked fruits.; vs Malacothamnus: Sidalcea is herbaceous in meadows; Malacothamnus is a woody shrub in chaparral.; vs Calochortus: Sidalcea is a dicot with 5-petaled flowers; Calochortus is a monocot with 3-petaled flowers from bulbs.
Frequently asked questions
Is Sidalcea gigantea native to California?
Yes. Sidalcea gigantea is native to California (recorded as native).
When does Sidalcea gigantea bloom?
Sidalcea gigantea blooms Jul-Sep.
What plant family does Sidalcea gigantea belong to?
Sidalcea gigantea is in the Malvaceae family, genus Sidalcea.
Is Sidalcea gigantea rare or endangered?
Sidalcea gigantea carries California Rare Plant Rank 4.3, state rank S3.
What habitat does Sidalcea gigantea grow in?
Sidalcea gigantea grows in Moist to wet forested slopes, seeps, stream margins, meadows, mid to upper conifer forest.
Related species
Other California species in the same genus, family, or bioregion.
- Sidalcea glaucescens — Waxy checkerbloom
- Sidalcea hartwegii — Hartweg's checkerbloom
- Sidalcea hickmanii — Chaparral checkerbloom
- Sidalcea hickmanii subsp. anomala — Cuesta pass checkerbloom
- Sidalcea hickmanii subsp. hickmanii — Hickman's checkerbloom
- Sidalcea hickmanii subsp. napensis — Napa checkerbloom
Sources: Jepson eFlora · CalPhotos · CDFW CNDDB
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.