Sulphur Penstemon

Penstemon attenuatus

Native to:
United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Plantaginaceae
Genus:
Penstemon
Species:
Penstemon attenuatus
USDA Symbol:
PEAT3

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb , Subshrub
Height:
70 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
may,jun,jul,aug
Bloom Colors:
blue, purple, violet

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)

Reported Fauna Sightings

Bees: Two-form bumble bee (Bombus bifarius), White-shouldered bumble bee (Bombus appositus), Yellow bumble bee (Bombus fervidus), Yellow head bumble bee (Bombus flavifrons)

Garden & Ecology Notes

Wildlife Value:
bees, hummingbirds, butterflies
Deer Resistant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Resprouts from root crown following fire; found in fire-maintained mountain meadows and open forests.

Soil Requirements

Soil Type:
well-drained, sandy or rocky soil
pH:
6.0 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
prefers open, sunny locations

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–90 days
Germination Time:
14–30 days
Notes:
Seeds require light for germination; surface sow and do not cover deeply.

Pre-treatment: 90 or more days of cold moist stratification required. Seed should be covered, not surface sown, for higher germination rates.

Establishment: Germination rates vary based on stratification time, with longer periods resulting in higher germination. Light exposure does not appear to affect germination. Seed of some penstemon species loses dormancy after 2.5 years.

Source: npn.rngr.net

ORGHPS Germination Guide: Sow @ 20C. Germinates within 3 months. Requires light / surface sow (fine seed). | GA3 improves germination.

Source: Ontario Rock Garden & Hardy Plant Society