Sulphur Penstemon
Penstemon attenuatus
- Native to:
- United States
Unknown author Unknown author
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:
- 80 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- Medium
- Bloom Months:
- jun,jul,aug
- Bloom Colors:
- blue, purple
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, butterflies, hummingbirds
- Deer Resistant:
- Yes
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 — 30–60 days
- Germination Time:
- 14–30 days
- Notes:
- Seeds benefit from cold moist stratification for 4-8 weeks to improve germination.
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.