River Birch care — light, water, toxicity and hardiness

River Birch (Betula nigra) wants full sun and a drink about every 4 days once established. It is hardy in USDA zones 4 to 9. It is safe to have around pets.

Care facts
scientific nameBetula nigra
familyBetulaceae
categorytree
plant typeperennial
lightfull sun
water cadence days4
mature height cm2000
min zone4
max zone9
frost toleranttrue
toxic to petsfalse
toxic to humansfalse
ediblefalse

How often should I water River Birch?

The heat-tolerant birch; peeling bark; likes wet feet.

Who eats it

Palatable to browsing animals such as deer: medium. Palatable to grazing animals: low. Palatable to people: no.

What it needs

Its shade tolerance is high. Its moisture use is high. Its drought tolerance is low. It wants at least about 30 inches of rain a year. Above roughly 80 inches of annual rain it struggles. It tolerates soil down to pH 3.0. It tolerates soil up to pH 6.5. Its fertility requirement is medium. Adapted to coarse, sandy soils: yes. Adapted to medium, loamy soils: yes. Adapted to fine, clay soils: yes. Its tolerance of waterlogging is medium. It needs at least 150 frost-free days. Its fire tolerance is medium. Fire resistant: no. It has been recorded down to -31°F. It suppresses neighbours chemically: no.

How it grows

It grows as a multiple stem form. Its growth rate is rapid. Its lifespan is short. It puts on most of its growth in spring and summer. It spreads by seed at a rapid rate. It spreads vegetatively at a slow rate. It resprouts after damage: yes. Coppices: yes. At maturity it reaches about 70.0 feet. By twenty years it is about 35 feet. Its roots go down at least 20 inches. Its shape is erect. It holds its leaves through winter: no.

What it looks like

It blooms in mid spring. The flowers are brown. Conspicuous in flower: no. The foliage is green. The foliage texture is medium. In summer the canopy is moderate in porosity. In winter it is porous in porosity. Fall colour: no. The fruit or seed is brown. Fruit begins in spring. Fruit finishes by spring. It fruits high. The fruit persists on the plant: no. The fruit is conspicuous: no.

Growing more of it

Propagated by seed: yes. Propagated by cuttings: yes. Propagated by container: yes. Propagated by bare root: yes. Propagated by bulb: no. Propagated by corm: no. Propagated by tubers: no. Cold stratification required: no. Seedling vigour is high. Commercial availability: routinely available.

Source: Drafted from US Cooperative Extension horticulture guidance; pending HUMAN-05 review (issue 280) · ASPCA Toxic and Non-Toxic Plant List · 2026-09-02