Idaho Locust
Robinia x ambigua 'Idahoensis'

Family: Papilionaceae (pa-pil-ee-uh-NAY-see-ee)
Genus: Robinia (roh-BIN-ee-uh)
Species: x ambigua
Cultivar: Idahoensis

Category
Trees

Foliage Color

Bloom Characteristics
This plant is attractive to bees, butterflies and/or birds
Flowers are fragrant

Water Requirements
Average Water Needs; Water regularly; do not overwater

Where to Grow

Height
20-30 ft. (6-9 m)
30-40 ft. (9-12 m)

Spacing
20-30 ft. (6-9 m)

Hardiness
USDA Zone 4a: to -34.4 C (-30 F)
USDA Zone 4b: to -31.6 C (-25 F)
USDA Zone 5a: to -28.8 C (-20 F)
USDA Zone 5b: to -26.1 C (-15 F)
USDA Zone 6a: to -23.3 C (-10 F)
USDA Zone 6b: to -20.5 C (-5 F)
USDA Zone 7a: to -17.7 C (0 F)
USDA Zone 7b: to -14.9 C (5 F)
USDA Zone 8a: to -12.2 C (10 F)
USDA Zone 8b: to -9.4 C (15 F)

Sun Exposure
Full Sun

Danger
Seed is poisonous if ingested
Parts of plant are poisonous if ingested

Bloom Color
Rose/Mauve

Bloom Time
Late Spring/Early Summer

Foliage
Grown for foliage
Deciduous
Smooth-Textured

Other details

Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)

Patent Information
Non-patented

Propagation Methods
From hardwood cuttings
From seed; direct sow outdoors in fall

Seed Collecting
Allow pods to dry on plant; break open to collect seeds
Seed does not store well; sow as soon as possible