When it comes to adding productive trees to your garden, it’s easy to just think of fruit trees. But nut trees provide a productive and nutritious addition to the harvest each year and there’s a nut tree to suit every climate and situation.
Walnuts, almonds, pecans, macadamias or pistachios, it’s hard to meet a nut you can’t love. Nut trees have been grown right across the world for centuries and Australia is lucky enough to grow most common nut varieties. Our commercial nut industry has seen rapid expansion in the last ten years thanks to growing demand for plant-based milks and foods, and recommendations from health professionals to include nuts as part of a healthy diet. Their versatility has meant most of us (those with allergies excluded, of course) would be hard-pressed to go a week without some type of nut making its way into our diet. So what about growing them at home?
Why Grow Nuts?
Nut trees are a great addition to a productive garden. They are long-lived and surprisingly low-maintenance if you choose the right variety for your climate. They provide valuable summer shade, beauty and structure in a garden and increasingly bountiful harvests once mature. They are a perfect option for the upper canopy layer in a food forest or a mixed-crop orchard, and can even have a place in small backyards. While most varieties will take a few years to start producing, once established you could be picking many kilograms of nuts to be eaten fresh or stored for the coming months.
While it’s common knowledge that peanuts are a legume and not a nut, it may surprise you to learn that some of the most popular varieties of nuts are actually seeds. Walnuts, cashews, pistachios and almonds are all examples of drupe seeds. A drupe is a fleshy fruit with a hard inner seed and includes stone fruit.
True nuts are those like chestnuts and hazelnuts which develop a hard outer shell and don’t split open when ripe – this also includes acorns from oak trees. Other seeds masquerading as nuts include Brazil nuts and pine nuts. Confused? Don’t be – the general consensus is that we still call them nuts for simplicity’s sake.
A Healthy Addition
In comparison to many other foods we may grow at home, nuts punch well above their weight. They are a fantastic source of healthy unsaturated fats, minerals and vitamins, as well as antioxidants, protein and fibre. Nuts are also a source of zinc, niacin and iron for people who avoid consuming meat.
Most nuts can be eaten raw or roasted, or can be ground into a flour, meal or paste for added versatility. Soaking nuts in water helps to break down phytates contained in their skins, an enzyme which may hinder the availability of vitamins and minerals from nuts when eaten. This explains the trend of ‘activating’ nuts, which is soaking nuts and drying them at very low temperatures. By doing so, it reduces the effects of phytates and makes the nuts somewhat more digestible, but for someone with good gut health and a well-rounded diet the increase in nutritional value is minor.
Which Nut To Grow?
Here in Australia, we are able to grow most of the common nut varieties thanks to our wide-ranging climate. Nut trees for a cool-temperate climate include hazelnut, chestnut and walnut. Warm-temperate climates favour pine nuts, pecans and almonds, with macadamia and cashews preferring a subtropical or tropical climates.
For the arid and semi-arid zones, pistachios and sandalwood nuts are great options. The growing range for many of these nuts is greater than their preferred climates, so if you are in southern Australia and want to grow macadamias, don’t be deterred – pick the most suitable spot you have and give it a try.
Once you’ve established which nuts will grow in your climate, consider the space you have available. Some nut trees will mature into very large trees and take significant pruning to keep to a manageable size for a backyard. If you are tight on space, varieties like hazelnuts, almonds, cashews and pistachios are smaller trees or large shrubs that fit well in a backyard. There are increasingly more varieties of nuts grown on dwarfing rootstock, too, with almonds and macadamias two commonly found options.
Another thing to consider is how quickly you want a harvest. Some nut trees won’t start to bear fruit for many years and won’t reach maximum productivity for up to ten years (see breakout) when the tree is mature. For quick harvests consider almonds, cashews or pistachios, which will start to bear nuts in as little as two years.
While most nut varieties we recognise originate from other parts of the globe, there are several nuts native to Australia. Macadamias are a huge export success for Australia, and a significant proportion of the world’s macadamia trees originate from here. A traditional food source for Indigenous Australians, they have one of the highest energy values of any nut.
The Bunya Pine (Aracauria bidwilli) is a large tree to 45 metres in height preferring the south east and northern areas of Queensland. Bunya Pines produce very large pine cones of up to ten kilograms each containing numerous Bunya nuts. These nuts are highly nutritious and can be eaten fresh, cooked or ground into flour. The trees are extremely long lived – hundreds of years – in the right conditions, and very slow to mature, so consider them an investment in future generations if you grow one.
Sandalwood is a lesser known native nut that grows on the same Sandalwood tree used for fragrance production in arid and semi-arid climates. The nuts grow throughout autumn and are ready for harvest by late winter. They are a creamy nut that can be eaten raw or roasted, they contain very high levels of good fats and twice the protein of macadamia nuts.
Bare Rooted Or Potted?
Nut trees can be purchased bare-rooted in autumn and winter or potted year round. Bare-rooted trees will be supplied as dormant young trees with their roots clipped and wrapped in a medium to keep them damp. They will need to be planted soon after purchase or kept in cool storage. Often the availability of nut varieties and cultivars will be greater with bare-rooted plants, and they are easier to purchase from tree nurseries online if you can’t source them locally. Buying nut trees in pots can be done at any time of the year, though they will need extra care and water if you plant them out in spring or summer. Unless you are looking for a larger tree to visually bring together a space, opting for a young tree can sometimes be a better option – larger trees will often take longer to establish.
Planting And Maintenance
Choose a spot in your garden that gets at least six hours of sun per day and is protected from strong winds and heavy frosts, which may damage trees that flower early in the spring as this will result in reduced harvests.
Most nut trees will tolerate a pH range of between 6.5 and 7.5, although cashews, pecans and chestnuts can handle slightly more acidic soils. Free-draining soil is best in order to avoid potential issues with root-rot or fungus infestations.
Most nut trees have an extensive root system making them quite drought-hardy and able to grow well in soils that are lower in organic matter. The addition of well-rotted manure or good quality compost in the top part of the planting hole, followed by deep watering and mulching (in spring or summer) will benefit tree establishment.
The best time to plant potted nut trees is during autumn. This allows the tree to make the most of the soil warmth to get a head start on root establishment before the soil cools and deciduous trees enter dormancy.
Nut tree maintenance is similar to that of fruit trees – water them deeply and keep them mulched in the hottest parts of the year and when setting and growing nuts. They are generally hardier than fruit trees but still benefit from yearly additions of pH-suitable fertiliser and compost.
Pruning nut trees is particular to variety. Some nuts, like almonds, fruit on second-year wood and benefit from having old wood removed in the same way a peach or plum might. Hazelnuts put up suckers, which are best removed to maintain productivity. Others, such as walnuts, need little pruning once formative shaping is done. Pecans can grow to be enormous trees – up to 30 metres in good conditions – and will need to be kept in check if you want to be able to harvest the whole tree, otherwise it’s some for you and some for the wildlife.
As a general rule, prune any nut tree for good airflow through the foliage to reduce the incidence of fungal issues and pest infestations. Late winter is the time to prune deciduous nut varieties, as the tree is beginning to stir from dormancy and the rising sap will heal the pruning wounds quickly, minimising the risk of disease.
There are various pests and diseases that trouble nuts depending on your variety. Rodents and birds are standard pests, and may mean you need to net your trees. Fungal infections like rust are more likely in trees that aren’t kept pruned for airflow, especially in humid environments.
Harvesting Nuts And Storage
All nuts require some level of processing after harvest to remove them from their outer hulls and shells. On a commercial scale this is mechanised, but at home it can require either patience or a strong arm to crack them, depending on your nut variety.
Some nuts, like green almonds, can be picked and eaten when only partly developed as a way to extend the harvest from the tree. Green almonds are immature almonds that have not yet fully hardened and have a fresh, grassy taste with a somewhat jelly-like consistency. The whole almond can be eaten, including the outer fuzzy part. Another immature nut delicacy is the traditional English pickled walnut – immature green walnuts brined and preserved.
Nuts picked and eaten straight from the tree will be the most fresh and delicious, but stored correctly they can last for many months. Keeping nuts (either in their shells or shelled) in a cool dark place in the short term, or in your fridge or freezer for extended storage, reduces the likelihood of the fats in the nuts going rancid.
If you can’t grow nuts, avoid pre-roasted versions; purchasing them raw and roasting them yourself will make sure their freshness and nutritional profiles are the best they can be.