Thunberg's Geranium

Geranium thunbergii

Native to:
China, Japan, Korea, Kuril Is., Nansei-shoto, Taiwan

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Geraniaceae
Genus:
Geranium
Species:
Geranium thunbergii
USDA Symbol:
GETH3

Growth Characteristics

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

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)

Keystone Species Ranking

Caterpillar Keystone:
★★★☆☆ Butterfly & moth species supported by this genus (NWF)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies
Fall Color:
red

Soil Requirements

Soil Type:
rich, well-drained loamy soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
good drainage required
Moisture:
consistently moist
Notes:
Prefers shaded or semi-shaded areas

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days
Notes:
Seeds benefit from cold stratification for 4-8 weeks to break dormancy.

ORGHPS Germination Guide: Sow @ 20C. Germinates within 3 months.

Source: Ontario Rock Garden & Hardy Plant Society