When to plant Walnut Tree?

Walnut trees thrive in full sun and need a sheltered position away from late-spring frosts, which can damage young shoots and flowers. Choose a site with plenty of space—mature trees reach 10–25 metres tall with a spread of 8–15 metres, so plant at least 10 metres from buildings, boundaries, and other large trees. Avoid planting near vegetable beds or ornamental borders; walnut roots release juglone, a substance toxic to many plants including tomatoes, potatoes, and rhododendrons. Walnuts tolerate a range of soils—loam, clay, and chalky ground all suit them—but drainage must be good. Waterlogged roots will rot. Dig a planting hole twice the width of the root ball and the same depth. Break up compacted soil at the base and incorporate a bucketful of well-rotted compost or manure into the backfill, but avoid adding fertiliser at planting time. Plant bare-root trees in October or November while the soil is still warm and the tree is dormant. Container-grown specimens can go in during the same period for best results. Position the tree so the soil mark on the stem sits level with the surrounding ground—planting too deep encourages stem rot. Spread the roots out naturally, backfill with the improved soil, and firm gently with your heel to eliminate air pockets. Water thoroughly after planting, applying at least 20 litres. Drive in a sturdy stake at a 45-degree angle to avoid the root ball, and secure the trunk with a tree tie, leaving room for growth. Apply a 7–10 cm layer of well-rotted compost or bark mulch around the base, keeping it clear of the trunk itself to prevent rot.