Limestone Beardtongue
Penstemon calcareus
- Native to:
- United States
Steve Matson https://www.inaturalist.org/people/matsonburger (www.inaturalist.org)
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Plantaginaceae
- Genus:
- Penstemon
- Species:
- Penstemon calcareus
- USDA Symbol:
- PECA5
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Forb/herb
- Height:
- 50 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- High
- Bloom Months:
- may,jun,jul
- Bloom Colors:
- lavender, purple, blue
Wildlife Benefits
- Bees:
- ★☆☆☆☆ Documented bee visitation (GBIF)
Garden & Ecology Notes
- Wildlife Value:
- bees, hummingbirds
- Deer Resistant:
- Yes
Soil Requirements
- Soil Type:
- rocky, well-drained calcareous soil
- pH:
- 6.5 - 8.0 (neutral to slightly alkaline)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- native to limestone-rich areas
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–90 days
- Germination Time:
- 14–30 days
- Notes:
- Cold stratification improves germination rates. Surface sow as seeds may require light.
The above propagation data sourced from Claude AI
Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).
Source: Claude AI
ORGHPS Germination Guide: Most interbreed and seed may not be what is labelled; germinates best with stored seed, even as long as 10 years at 20°