Broadkeel Milkvetch

Astragalus platytropis

Native to:
United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Fabaceae
Genus:
Astragalus
Species:
Astragalus platytropis
USDA Symbol:
ASPL3

Growth Characteristics

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

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (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

Shasta Blue (Plebejus shasta)

Garden & Ecology Notes

Wildlife Value:
bees, native pollinators
Deer Resistant:
Yes

Soil Requirements

Soil Type:
rocky, well-drained, nutrient-poor soil
pH:
6.0 - 8.0 (neutral to slightly alkaline)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
commonly found in alpine and subalpine regions

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Scarification:
Seed coat scarification required before sowing
Germination Time:
14–30 days
Notes:
Seeds have hard coats typical of legumes. Scarification followed by cold stratification improves germination rates.

The above propagation data sourced from Claude AI