Walnut trees are a long lived tree that that grow well in areas of Australia with a Mediterranean climate. Depending on conditions they will reach between 15 and 25m over time, with tree reaching well over 100 years.
A deciduous tree the walnut ‘Juglans regia’ is valued for both nut production as well as for timber for fine furniture in Australia they are grown for commercial nut production in Tasmania, Victoria, Southern NSW, around Adelaide and also in southern WA.
Walnut trees are also grown in many home gardens as an ornamental tree, attractive spreading canopy, nice foliage and the long lived nature of the tree are all good characteristics. It is the flesh of the nuts that makes these a valuable crop.
In good soil and the right climate, these are a medium to large sized tree, producing good sized crops. In poorer soils the trees will be smaller and nut production will be limited. If you are looking for a naturally smaller growing tree then Howard may be the one to look for.
Growing Conditions
Walnut trees perform best in deep, well-drained soils that are rich in organic matter. In good soil with consistent moisture, they will grow into medium to large trees and produce reliable crops. In poorer or shallow soils, growth will be slower, trees will remain smaller, and nut production will be reduced.
A warm, temperate climate with cool winters is ideal. Walnut trees require a period of winter chill to set fruit properly, so they are best suited to southern regions rather than tropical or subtropical areas. They also prefer a position in full sun, protected from strong winds where possible.
Tree Size and Spacing
Given their eventual size, walnut trees need plenty of space to grow. In a home garden setting, they should be planted well away from buildings and other large trees. In orchards, spacing is important to allow for good light penetration and air movement, which helps with both growth and disease management.
If space is limited, selecting a naturally smaller growing variety such as ‘Howard’ may be a better option.
Varieties
Walnut trees grown for nut production are usually grafted rather than grown from seed, as this ensures consistent quality and earlier fruiting. There are a number of well-known varieties available in Australia.
Popular varieties include Chandler and Tulare, both widely used in commercial plantings. These may be grown on their own roots or grafted onto Paradox rootstock, which is known for its vigour and adaptability.
Other varieties such as Howard and Franquette are also available. Howard is often chosen for its more compact growth habit, making it suitable for smaller spaces, while Franquette is valued in cooler climates and can assist with pollination in mixed plantings.
Pollination and Nut Production
Walnut trees can vary in their pollination requirements. Some varieties are partially self-fertile, but better nut set is usually achieved when more than one variety is planted. Cross-pollination improves both yield and consistency of crops.
Grafted trees will generally begin to produce nuts within 4 to 7 years, depending on conditions. Seed-grown trees can take considerably longer and are less predictable.
Care and Maintenance
Once established, walnut trees require relatively low maintenance, but a few basic practices will help improve growth and productivity.
- Watering: Young trees need regular watering during dry periods. Established trees are more tolerant but still benefit from deep watering in extended dry conditions.
- Fertilising: Applying organic matter or a balanced fertiliser in spring can support healthy growth.
- Pruning: Minimal pruning is required, mainly to remove dead or damaged wood and to shape the tree when young.
- Weed control: Keeping the base of the tree free from competition will help early establishment.
Walnut Trees are available for sale from the following nurseries
55 McDougal Rd Neerim South Victoria 3831 PH: (03) 56281507
Advanced ornamental trees and garden designs and concept plans. Direct to your property combined with specialist knowledge and outstanding service.
www.blericktreefarm.com.au
Carey Gully, Adelaide Hills.
Family business selling a large range of deciduous trees in pots 1-4m high. Crepe myrtle specialist. Includes Ornamental pears & plums, Red maples, Japanese maples, Gingko, Cercis, Ash, Birch, Crab apples, Weeping cherries, Gleditsia, Liquidambar and more. Hedging plants, evergreen trees & fruit trees.
www.adelaidetreefarm.com.au
"Propagation and Production of Native and Exotic Trees
with Natural Root Systems from 2 to 2,000 lts."
www.njrivett.com.au