Aaron's Rod

Thermopsis villosa

Native to:
United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Fabaceae
Genus:
Thermopsis
Species:
Thermopsis villosa
USDA Symbol:
THVI

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb
Height:
150 cm
Light Requirements:
Full Sun,Part Shade
Drought Tolerance:
Medium
Bloom Months:
may,jun
Bloom Colors:
yellow

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)
Caterpillars:
★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)

Host Plant for Caterpillars

Wild Indigo Duskywing (Erynnis baptisiae)

Reported Fauna Sightings

Bees: Brown-belted bumble (Bombus griseocollis)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies
Deer Resistant:
Yes

Soil Requirements

Soil Type:
rich, well-drained loamy soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Scarification:
Seed coat scarification required before sowing
Germination Time:
14–30 days
Notes:
Scarification of the hard seed coat is recommended before cold stratification. Seeds may germinate erratically without pretreatment.

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: Sow immediately, Either the viability of these seeds is short or the species propagates best with fresh seed. Stored seed might be coaxed into germination with temperature cycling and patience. Sow @ 20°C. Seed germinates within 3 months Resents transplanting. 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. * tiny seed should be scarified with sandpaper, pot deeply; protect from damping off

Source: Ontario Rock Garden & Hardy Plant Society