Walnut trees are a deciduous broadleaf tree native to south-east Europe to south-west China.
Scientific name: Juglans regia Family: Juglandaceae
The best wood is at the base of the walnut tree, so walnut trees are often dug up for timber, rather than felled.
Walnut trees can grow to 35m. Walnut trees typically have a short trunk and broad crown, though can be narrower if grown in a woodland situation. All walnuts will grow into large trees given the right conditions and space. Growth rates vary considerably depending on species and site conditions. The bark is smooth and olive-brown when young, developing fissures and fading to silver-grey with age. Twigs are stout, green and curving. These beautiful trees also provide shade in the landscape with their large, arching limbs.
Leaves: shiny and pinnate (feather-like), with 5-9 paired oval leaflets and one ‘terminal’ leaflet at the end.
Flowers: male flowers are drooping yellow-green catkins 5–10 cm long, and the female flowers appear in clusters of 2-5.
Fruits: pollinated by wind, female flowers develop into a fruit with a green, fleshy husk and a brown, wrinkled walnut. A mature tree will produce 50 to 80 pounds of nuts yearly. Walnut trees won’t start producing nuts until they are about 10 years old, with peak production around 30 years old.
All walnut species grow best on fertile soils that are deep (90cm minimum) and well drained. Walnut trees have an extensive root system and as such do not need to be watered often — only if the top 2 inches of soil have dried out. Prune any dead or damaged limbs as the tree matures; otherwise, there is no need to prune. Add mulch as needed each spring.