Winterbeam

Sorbus airia

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Rosaceae
Genus:
Sorbus
Species:
Sorbus airia
USDA Symbol:
SOAI

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Tree
Height:
1500 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
apr,may
Bloom Colors:
white

Keystone Species Ranking

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

Garden & Ecology Notes

Wildlife Value:
birds, small mammals
Fall Color:
red, orange

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:
prefers cool, temperate climates

Propagation & Germination

Stratification:
Cold/moist stratification required — 60–90 days
Germination Time:
30–60 days
Notes:
Seeds require cold stratification for 2-3 months to break dormancy.

ORGHPS Germination Guide: Place on damp paper towel in plastic bag for 6 weeks in fridge - should germinate in cold

Source: Ontario Rock Garden & Hardy Plant Society