The Walnut Tree Company
Potash Farm

Planting and Caring for your Walnut Tree

All species grow best on fertile soils of pH 5.5-7.5, and 90cm or 3 ft deep.

Avoid frost pockets in valley bottoms and water-logging prone areas. They will not grow well in compacted soils, or those with a gravel layer or iron pan close to the surface.

Exposed sites and those with steep slopes should also be avoided, whilst gentle slopes near the valley bottom are optimal as cold air is drained from the trees and water availability is high.

Prepare the site before planting by breaking up any compacted soil, removing weeds and improving drainage if necessary. When planting, it is a good idea to mix a mulch or compost to the soil.

Walnut Trees are best ‘pit’ planted, and should be placed in a pit several inches wider and deeper than the root ball. Place the tree centrally and ensure the roots are evenly distributed, before watering in well, continuing to do so over the first growing season.

Trees grown for fruit production need a lot of space for crown development, usually a minimum of 7m x 7m (23ft x 23ft) between trees (204 trees per hectare) and grown as a monoculture. Trees grown for timber production are normally spaced a minimum of 5m x 5m (16ft x 16ft) between each tree (400 trees per hectare) as well as being inter-planted with other trees and shrubs to encourage straight growth.

Trees can grow up to 25m (80ft) or more, and can have very wide spreading crowns (canopies). Although growth rates vary considerably depending on species and site conditions, hybrids, the most rapidly growing, can increase in growth by over a centimetre each year in diameter and by several feet in height.

It is a good idea to provide the tree with a good quality mulch or nitrogen rich fertiliser early in the spring. Do not fertilise in late summer, as this can encourage late vegetative growth that can be susceptible to frost damage.

Pruning should be carried out only in mid winter or midsummer. Start by removing dead, damaged and badly forked branches, and don’t remove more than 20% of the crown at one time.