Sulphur-Flower Buckwheat

Eriogonum umbellatum

Native to:
Canada, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Polygonaceae
Genus:
Eriogonum
Species:
Eriogonum umbellatum
USDA Symbol:
ERUM

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb , Shrub , Subshrub
Height:
30 cm
Light Requirements:
Full Sun,Part Shade
Drought Tolerance:
High
Bloom Months:
jun,jul,aug,sep
Bloom Colors:
yellow, cream, white
Ground Cover:
Yes
Landscaping Shrub:
Yes

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)
Caterpillars:
★★☆☆☆ Recorded caterpillar host plant (HOSTS Database)

Keystone Species Ranking

Pollen Specialist Bee Keystone:
★★★★☆ Native pollen specialist bee species supported by this genus (NWF)

Host Plant for Caterpillars

Chalceria heteronea, Comstock's hairstreak (Callophrys comstocki), Dotted Blue (Euphilotes enoptes), Lembert's hairstreak (Callophrys lemberti), Lupine Blue (Plebejus lupini), Melissa Blue (Lycaeides melissa), Sheridan's green hairstreak (Callophrys sheridanii), Square-spotted blue (Euphilotes battoides), Western Green Hairstreak (Callophrys apama), Western Green Hairstreak (Callophrys affinis)

Reported Fauna Sightings

Bees: Hunt's bumble bee (Bombus huntii), Red-belted bumble bee (Bombus rufocinctus), Two-form bumble bee (Bombus bifarius), Yellow-faced bumble bee (Bombus vosnesenskii) Butterflies:Euphilotes sp. (Euphilotes Mattoni), Glaucon Blue (Euphilotes glaucon), Half-moon Hairstreak (Satyrium semiluna), Rocky Mountain (Euphilotes ancilla)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies, birds
Deer Resistant:
Yes
Fall Color:
red, bronze
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Resprouts from woody root crown following fire; common in fire-adapted sagebrush and montane communities.

Soil Requirements

Soil Type:
rocky, well-drained, nutrient-poor soil
pH:
6.0 - 8.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
Thrives in arid, mountainous regions

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–90 days
Germination Time:
14–60 days
Notes:
Seeds germinate best with cold stratification; light may improve germination rates.

The above propagation data sourced from Claude AI

Pre-treatment: Seeds are placed in cold stratification or imbibed in water for 10 minutes prior to a 60 to 90 day cold, moist stratification. Some protocols suggest no treatment.

Establishment: Germination rates and times vary significantly between protocols and treatments. Some protocols suggest winter conditions are necessary for germination, while others do not. Germination rates are generally higher with winter conditions. Seed collection times and methods also vary, with some suggesting collection when the inflorescence is dry and a reddish-orange color, and others suggesting collection when the corolla becomes papery. Seed cleaning techniques vary as well.

Source: npn.rngr.net

ORGHPS Germination Guide: Sow @ 20°C for 3 months, then place @ 4°C for 3 months. Resents transplanting. * must be stored at 4°C

Source: Ontario Rock Garden & Hardy Plant Society