Eriogonum umbellatum
A drought-tolerant, mat-forming perennial native to western North America, with sulfur-yellow flower clusters that attract bees and butterflies and thrives in hot, dry, well-drained rocky or sandy soils.
Common Names
Sulphur Buckwheat, Sulfur Buckwheat, Sulphurflower Buckwheat, Sulphur-Flower Buckwheat, Sulphur Flower, Sulphur Wildbuckwheat, Slender Buckwheat, Umbrella Plant, Umbrella Desert Buckwheat, Buckwheat Bush
Summary
Sulphur buckwheat is a native western North American perennial forming low mats, with basal green leaves that are gray beneath and sometimes woolly; flower stems rise 3–16 inches to bear flat-topped umbels of sulfur-yellow flowers aging to orange-red, blooming June–October with elevational variation. It is highly variable with many varieties, drought-tolerant and suited to dry, rocky soils, thriving in full sun to light shade; its habitat includes dry rocky slopes, sagebrush flats, and subalpine ridges, and it attracts bees and butterflies while serving as a larval host for several butterfly species; hardy to USDA zones 4–8.
Cultivation favors full sun and well-drained rocky or sandy soils, with extreme drought-tolerance after establishment and tolerance of low irrigation. Propagation is by seed with cold stratification (8–24 weeks); direct seeding or plug planting are common, and first-year weed control is important. Landscape uses include rock gardens, groundcovers, erosion control, and habitat plantings; it attracts bees and butterflies and provides wildlife forage; pests are minimal but rust and powdery mildew can occur.
Lifecycle
Perennial
Height
4 inches to 4 feet
Spread
1-3 feet
Hardiness Zones
Zones 4-8
Sunlight Requirements
Ideally full sun to partial shade.
Soil Type
Well-drained, sandy or gravelly soil with low fertility
Soil Drainage
Well-drained soils (sandy or gravelly); avoid poorly drained or wet soils.
Soil pH
6.5-9.0
Bloom Color
Yellow
Bloom Time
Summer to Fall
Foliage Color
Green, gray-green, silver-green
Fall Foliage Color
Red
Leaf Lifecycle
Evergreen broadleaf
Growth Rate
Moderate growth; overall relative growth rate about 0.40 mg/mg/week with tissue values ranging from 0.38 to 0.48 mg/mg/week.
Seasons of Interest
Summer and Fall
Propagation Methods
Seeds, Division, Soft-wood cuttings, Direct seeding, Transplanting plugs or container stock
Attracts Wildlife
Attracts bees, butterflies, other pollinators, birds
Taxonomy
- Taxonomic Rank
- Species
- Author
- Torr.
- Publication
- Ann. Lyceum Nat. Hist. New York 2: 241 (1827)
Superior Taxa
- Kingdom
- Plantae
- Subkingdom
- Pteridobiotina
- Phylum
- Angiosperms
- Order
- Caryophyllales
- Family
- Polygonaceae
- Genus
- Eriogonum
Inferior Taxa
Eriogonum umbellatum var. aureum Eriogonum umbellatum var. bahiiforme Eriogonum umbellatum var. cladophorum Eriogonum umbellatum var. cognatum Eriogonum umbellatum var. covillei Eriogonum umbellatum var. dichrocephalum Eriogonum umbellatum var. dumosum Eriogonum umbellatum var. ellipticum Eriogonum umbellatum var. glaberrimum Eriogonum umbellatum var. haussknechtii Eriogonum umbellatum var. hypoleium Eriogonum umbellatum var. majus Eriogonum umbellatum var. minus Eriogonum umbellatum var. modocense Eriogonum umbellatum var. munzii Eriogonum umbellatum var. nevadense Eriogonum umbellatum var. porteri Eriogonum umbellatum var. smallianum Eriogonum umbellatum var. speciosum Eriogonum umbellatum var. subaridum Eriogonum umbellatum var. torreyanum Eriogonum umbellatum var. versicolor
Synonyms
Eriogonum cupreum Eriogonum polyanthum Eriogonum tolmieanum Eriogonum umbellatum var. crandallii Eriogonum umbellatum var. monocephalum Eriogonum umbellatum subsp. polyanthum Eriogonum umbellatum subsp. subaridum Eriogonum umbellatum var. tolmieanum Eriogonum umbellatum subsp. umbellatum Eriogonum latum Eriogonum umbellatum var. californicum Eriogonum umbellatum var. umbellatum