Cold hardiness

Future

2050

2100

These values are location-based: this location's current hardiness is the baseline, and the 2050 value is a projected future climate for this same location.

Now

Zone 6b

USDA

Published baseline for this location from 1991-2020.

Source: USDA Plant Hardiness Zone Map 2023 (1991-2020 climatology) via ArcGIS FeatureServer

Well-suited

2050

Zone 7a

Plotwright

Projected zone for this same location in 2050 (2041-2070) using SSP3-7.0 (regional rivalry).

Well-suited

In plain terms: This location is in Zone 6b today. Its hardiness profile is cold winters, and coldest nights are typically around -3°F. By 2050, the projected hardiness zone is Zone 7a based on SSP3-7.0 (regional rivalry). That is a +0.5-zone shift from Zone 6b to Zone 7a by 2050.

✓

Well-suited today and still thriving in 2050.

Heat tolerance

Future

2050

2100

Heat tolerance values are location-based too: heat days today are observed at this site, and the 2050 value projects this same location under a future climate.

Loading AHS heat-zone data for this location...

Where this plant fits

Suitable across 41 ecoregions — 40 climate-resilient through 2070 · 1 suited today. Best matches first.

Appalachian mixed mesophytic forests

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Appalachian-Blue Ridge forests

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Arizona Mountains forests

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Atlantic coastal pine barrens

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Blue Mountains forests

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Canadian Aspen forests and parklands

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Central Pacific Northwest coastal forests

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Central Tallgrass prairie

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Central-Southern Cascades Forests

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Chilean Matorral

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What it needs

Conditions

Light

Full sun

Water

Moderate water

Spacing

480"

Habit

Large single-trunked deciduous shade tree with an oval to rounded crown

Care tips

•

Give it serious room — at 75-100 feet tall and wide it belongs in an open landscape, never as a street or small-yard tree.

•

Keep juglone-sensitive plants (azaleas, rhododendrons, blueberries, peonies, tomatoes) out of the root zone.

•

Expect about 20 years before a large nut crop; this is a long-horizon shade and timber tree.

Lifecycle

Planting

Plant in full sun in moist, organically rich, well-drained soil. Intolerant of shade. Give it room — at 75-100 feet tall and wide it is a tree for expansive landscapes, not a street or small-yard tree.

Transplanting

Difficult to transplant because of the deep taproot; move only young trees and disturb the taproot as little as possible.

Early growth

Water through establishment. Keep juglone-sensitive plants (azaleas, rhododendrons, blueberries, peonies, and tomato-family crops) well away from the root zone.

Maturity

Reaches 75-100 feet (occasionally to 125 feet) with a broad oval to rounded crown. Young trees sometimes begin producing nuts at 4-6 years old, but a large nut crop typically takes about 20 years.

Propagation

Grown from the nuts (seed); the deep taproot makes seed-grown trees the standard path.

Pollination

Wind-pollinated

Monoecious and wind-pollinated: yellowish-green male catkins and small female flowers appear May-June on the same tree (Missouri Botanical Garden PlantFinder). The flowers are insignificant and do not provide a nectar reward for bees or butterflies.

Plants don't grow alone

Larval host

Moth

Luna moth (Actias luna)

Larval host

Moth

Polyphemus moth (Antheraea polyphemus)

Larval host

Moth

Imperial moth (Eacles imperialis)

The Lady Bird Johnson Wildflower Center documents black walnut as a larval host for large silk moths (Saturniidae), naming the luna and regal moths; the imperial moth (Eacles imperialis) is a closely related polyphagous Saturniid that also uses walnut, mapped here as the nearest catalogued silk-moth host.

Seed forage

Mammal

Eastern gray squirrel (Sciurus carolinensis)

Shelter / habitat

Bird

Eastern songbirds (multi-species) (multiple species (Passeriformes))

The Lady Bird Johnson Wildflower Center lists black walnut as attracting birds; the large canopy provides cover and nesting structure for songbirds (the hard-shelled nuts themselves are eaten mainly by squirrels and other strong-jawed mammals rather than songbirds).

For people

Edible with preparation

Missouri Botanical Garden PlantFinder notes the nut meats are used in baked goods and confections; the extremely hard shells and staining green husks require cracking and cleaning before use. The prized dark wood is used for furniture, cabinets, gunstocks, and veneer, and the nuts, husks, and bark yield a brown dye.

Native range

Native across 39 US states + 1 CA province.

AHS heat range

1-11

Native ecoregions

Naturally belongs in 25 ecoregions — its native range crosses a state or province each one spans (not necessarily this exact habitat).

Appalachian mixed mesophytic forests

›

Appalachian-Blue Ridge forests

›

Atlantic coastal pine barrens

›

Canadian Aspen forests and parklands

›

Central Tallgrass prairie

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Chihuahuan desert

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Colorado Rockies forests

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Cross-Timbers savanna-woodland

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Eastern Canadian Forest-Boreal transition

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Eastern Great Lakes lowland forests

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Climate notes

•

Missouri Botanical Garden PlantFinder lists Juglans nigra for USDA zones 4 to 9 in full sun with medium water, growing 75-100 feet tall and wide; it prefers moist, organically rich, well-drained soil and is intolerant of shade.

•

Missouri Botanical Garden PlantFinder records its tolerances as rabbit and drought, and notes that black walnut produces juglone, which is toxic to azaleas, rhododendrons, blueberries, peonies, and solanaceous crops.

•

The Lady Bird Johnson Wildflower Center documents it native across roughly 39 US states (Massachusetts and Florida west to South Dakota and Texas) and into Ontario, in rich, moist woods and bottomlands.

In the designer

Growth over time

135-180" tall · 108-144" spread

Reads as an upright young tree; decades from full size and first large nut crops.

Design roles: Structure · Focal point

Seasonal interest

Spring

Summer

Fall

Winter

Filled = the plant has seasonal interest · ▾ now = your current season

Black walnut

At a glance

Related products

Why it matters

Cold hardiness

Heat tolerance

Where this plant fits

What it needs

Lifecycle

Pollination

Plants don't grow alone

For people

Native range

Climate notes

In the designer

Seasonal interest

Sources & citations