How to grow Walnut

Juglans regia · common walnut, Persian walnut, English walnut

A large nut tree, 10–25 m tall, grown for its walnuts, which fall in autumn as the husk splits. It starts bearing at 4–6 years but gives a good crop only after 15–20 years; its roots release juglone, which harms tomatoes and some other plants.

Quick facts

Type	Fruit tree
Family	Juglandaceae
Light	Full sun
Soil pH	6–7
Frost	tolerates light frost
Sowing to harvest	1460 days
Where it grows	Open ground

When to plant

Planted as a young plant from a nursery while it is dormant — in early spring before the buds open, or in autumn after leaf fall.

Harvest from September to November (northern hemisphere).

Care

Open ground

Stage	Watering	Temperature	Feeding
Growth	every 7 days	—	organic, at the start of the stage
Flowering	every 7 days	—	—
Fruiting	every 7 days	—	—
Harvest	every 7 days	—	—
Winter rest	—	—	—

Growing notes

Light

A light-demanding tree: full sun, at least six hours a day, in a spot sheltered from wind.

Soil

Deep, well-drained, permeable soil at least 1.5 m deep, with a pH of 6–7.

Care

Plant young: the deep taproot makes older trees hard to move, and plant two cultivars so their bloom overlaps. From the second year spread compost around the tree in spring, away from the trunk. Prune in winter, thinning crowded branches to let light in. Gather the nuts when the green hulls start to split and dry them.

How to tell it is ripe

The green husk cracks open, showing the brown, wrinkled shell.
Nuts start dropping to the ground.
Cut into a husk: on a mature nut it comes away cleanly from the shell.
Knock or shake the nuts down once the husks begin to split, gather fallen ones often wearing gloves because the husk stains skin, and start drying them within a day.

Pests and diseases of Walnut

Sources

Figures checked against these sources.