Pygmy Rose
Rosa bridgesii
Also known as: Cascade Rose
- Native to:
- United States
My-Lan Le (www.inaturalist.org)
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Rosaceae
- Genus:
- Rosa
- Species:
- Rosa bridgesii
- USDA Symbol:
- ROBR3
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Subshrub
- Height:
- 100 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- Medium
- Bloom Months:
- may,jun,jul
- Bloom Colors:
- pink
- Landscaping Shrub:
- Yes
Wildlife Benefits
- Bees:
- ★☆☆☆☆ Documented bee visitation (GBIF)
- Caterpillars:
- ★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)
Keystone Species Ranking
- Caterpillar Keystone:
- ★★★★★ Butterfly & moth species supported by this genus (NWF)
Host Plant for Caterpillars
American Swordgrass Moth (Xylena nupera), gray swordgrass (Xylena cineritia), Linden looper (Erannis tiliaria), Western tent caterpillar (Malacosoma californica)
Garden & Ecology Notes
- Wildlife Value:
- birds, bees, small mammals
- Fragrant:
- Yes
- Fire Ecology:
- Fire adapted — tolerates or benefits from fire
- Fire Notes:
- Resprouts from root crown following fire. Tolerates periodic fire in chaparral and montane habitats.
Soil Requirements
- Soil Type:
- rich, well-drained loamy soil
- pH:
- 5.5 - 7.0 (slightly acidic to neutral)
- Drainage:
- excellent drainage required
- Moisture:
- consistently moist
- Notes:
- native to mountainous regions with organic-rich soils
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 60–120 days
- Germination Time:
- 30–180 days
- Notes:
- Rosa seeds have variable dormancy and may require extended cold stratification. Germination can be erratic over multiple seasons.
The above propagation data sourced from Claude AI
Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).; then Cold-moist stratification for 60 days.
Source: Claude AI
ORGHPS Germination Guide: Requires scarification. Nick or rub between sheets of sandpaper. Requires soaking. Place in warm water until seeds swell, usually 24-48 hours. Discard water and any seeds that remain floating. Pulpy coat inhibits germination. Remove by soaking and rinsing in clean water for approximately 7 days. Discard water. * soak in hot water for 24 hours to scarify; plant at 32°C for 2-3 weeks, then 4°C for 4 months