Pruning fruit trees in Adelaide: winter, summer and what to cut

Adelaide is a great place to grow deciduous fruit. Our cool, wet winters give the trees the chill they need, and our long, dry summers ripen sweet fruit. A little pruning each year keeps trees healthy, productive and small enough to manage.

Before you start, read the guide to pruning basics for tools and how to make a clean cut. This guide is about what to cut on fruit trees, and when.

Winter pruning vs summer pruning

The time of year changes how a tree responds.

Winter pruning happens while the tree is dormant and bare, roughly June to August. With the leaves gone you can see the whole framework. The tree still has all its stored energy in the roots, so in spring it pushes that energy into fewer buds. The result is vigorous new growth. Use winter pruning to build shape on young trees and to renew older ones.

Summer pruning happens while the tree is in leaf, from around late spring through summer. Removing leafy growth reduces the energy the tree can make and store, so it slows the tree down. Use summer pruning to control size, to let light into the fruit, and to keep a tree at a height you can reach.

Many backyard growers now do both: a structural prune in winter and a size-control trim in summer.

Know where the fruit grows

Before you cut, work out where your tree carries its fruit. Cut off the wrong wood and you cut off the crop.

Spurs are short, stubby shoots with fat, rounded fruit buds. Leaf buds are slimmer and pointier. Once you can tell them apart, pruning makes a lot more sense.

Shaping the tree

Open vase for stone fruit

Peaches, nectarines, plums and apricots are usually grown as an open vase. There's no central trunk running up the middle. Instead, three to five main branches grow out and up from a short trunk, like the ribs of a bowl. The open centre lets sun into the middle of the tree, which ripens fruit and helps keep fungal disease down.

To build an open vase on a young tree:

1. At planting, cut the young tree back to about knee to thigh height, just above a bud.
2. In the first growing season, let shoots develop, then choose three to five well-spaced ones pointing in different directions. These become your main branches.
3. Remove other shoots that grow into the centre.
4. Each winter, shorten the main branches to an outward-facing bud to encourage branching, and keep the centre clear.

Central or modified leader for apples and pears

Apples and pears are often grown with a central leader, a single upright trunk with tiers of side branches, a bit like a Christmas tree. It's a strong shape but can get tall.

A modified leader is a common backyard compromise. You grow a central leader for a few years until the tree has a good set of main branches, then cut the leader back to a side branch to stop it going higher. You get a strong framework without a tree that disappears into the sky.

Pruning established trees

Peaches and nectarines

Because they fruit on last year's growth, peaches and nectarines need regular pruning to keep fresh shoots coming. In winter:

1. Remove the three Ds: dead, diseased and damaged wood.
2. Take out any shoots growing into the centre of the vase.
3. Remove some of the shoots that have already fruited, back to a new shoot lower down.
4. Shorten some of last summer's growth to encourage new fruiting wood for next year.

Peaches are often pruned in late winter in Adelaide, closer to bud swell. If your trees have had leaf curl, keep up with your usual spray program around bud swell.

Apples and pears

Apples and pears are slower and more forgiving. In winter:

1. Remove the three Ds and any crossing or rubbing branches.
2. Thin out crowded spurs on older trees, leaving the plumpest.
3. Shorten long, whippy growth on main branches by about a third to encourage new spurs.
4. Remove vigorous upright shoots (water shoots) that won't fruit for years.

Apricots and cherries: prune in late summer or autumn

Apricots and cherries are prone to fungal diseases such as silver leaf and to gummosis, where the bark oozes sticky gum. Silver leaf spores spread mostly in cool, damp weather and enter through fresh cuts.

So for these trees, skip winter pruning. Prune instead after harvest in late summer or early autumn, on a run of dry days. Wounds dry and seal faster in warm weather, before the wet season arrives. Keep the cuts as few and as clean as you can, and wipe your blades between trees.

Keeping trees small

You don't need a big yard for fruit. The backyard orchard approach keeps trees at about head height so you can pick, net and prune from the ground.

• Start early. Cut a young tree low at planting so it branches close to the ground.
• In summer, after the main flush of growth, cut new shoots back to about head height.
• Keep the tree no taller than you can comfortably reach.
• Choose dwarfing rootstocks or naturally compact varieties when buying.

A small tree gives you less fruit than a big one, but you'll actually pick it, and you can fit several varieties into the same space.

Citrus are different

Citrus need very little pruning. Remove dead wood and water shoots, and lift the skirt if you like, but there's no annual winter prune. See the guide to pruning citrus and evergreens.

A few reminders

• Never take more than about a third of a tree in one year.
• Clean up fallen fruit and diseased prunings; they can carry disease into next season.
• In summer, don't open a tree right up just before a heatwave. Exposed fruit and bark can sunburn.