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Black Walnut

Black Walnut

Black Walnut

(American Walnut)

Juglans Nigra

Occurs naturally in Southern Ontario and central and eastern USA. Occasionally planted in New Brunswick. Popular as a shade tree on larger properties and for its edible nuts. The wood is also valued in carpentry. The tree takes about 8 to 10 years for fruit production to begin. Tree parts and especially roots produce a chemical called juglone that inhibit growth of some plants in the root zone. Trees have both male and female flowers and are wind pollinated. Planting two or more trees will improve seed crop quantity through cross pollination. Mast seed crop every 2 to 3 years.

Additional information




Native to North America


Large (60-100ft)





Growth Rate



Long (over 100 years)

Hardiness Zones *

4, 5

Sun Exposure

Full Sun (over 6 hrs)

Soil Preferences *

Moist, Slightly Acidic, Well Draining

Soil Tolerances

Clay, Dry, Slightly Alkaline

Other Tolerances

Occasional Drought, Occasional Flooding

Ornamental Interest

Leaves (shape)

Wildlife Value

Birds (fruits/seeds), Butterfly Larvae (leaves), Small Mammals (fruits/seeds)

Human Value

Carpentry (wood), Edible (seed)

Seed Collection

Ordered Online, Personally in NB

Planting Considerations

Allelopathic, Intolerant of Full Shade, Messy Seed Litter

*Useful Links

Hardiness Zones – Canada’s Hardiness Zones

Soil Preferences РMulti-Purpose Soil Tester