Juglans nigra - Black Walnut

The Black Walnut is a handsome, fast-growing tree, native to North America, but planted in Britain as an ornamental. With its glossy hanging leaves and domed crown, it is an impressive sight in parkland and larger gardens. It needs warmer conditions to do well than the Common Walnut, but in good years will produce a good crop of nuts.

Site and soil

Requires deep rich soil and warmth. More tolerant of wet soils than the Common Walnut.

Height and spread

After 10 years: 8m x 4m
After 20 years 15m x 7m

Leaf and bark

The large leaves are pinnate, to 60cm, with 11-23 leaflets; they are glossy and aromatic. The bark is very dark grey-black and deeply fissured.

Flower, seed and fruit

The flowers are greenish catkins produced in May/June, followed by oval to round green fruits about 5cm across. These contain a husk which encloses the familiar walnut. The walnuts are more difficult to extract then the Common Walnut.

Uses

Ornamental tree, woodland. Walnut timber is very high quality and is used for furniture and veneers and the leaves and bark are used medicinally to treat skin complaints. The shell has been used in hair dyes, and both the leaves and husks yield dyes. Walnuts are grown commercially for their nuts.