More Healthy Fruit Trees!

If you’ve never eaten a home-grown white peach dripping with luscious juiciness before, then you have never really eaten a peach!

© Scott Hitchins

Factors to consider

1. Sun:  To produce fruit, fruiting plants need sunshine and usually plenty of it.  Although some forest species survive well with some dappled shade as they evolved as understorey species, all plants need some sun to survive and need even more of it if we keep picking bits off to eat.  Spend some time looking at your garden through the day: Which bits get sun most of the day?  Which bits get some sun and which get none?  The sun shines from the Northern part of the sky and is lower in the sky in winter than it is in summer so, first of all, find north.  Next, consider how fences, sheds, neighbours, etc, impact on your access to sunshine, as well as how trees you might want to plant will produce shade when grown: use this shade as an asset, rather than letting it create a problem.  You can’t change your yards aspect, but you can make the most of it.

2. Soil: Soil is something that you can change: mounding to improve drainage and adding composted organic material will go a long way to fixing any problems with the clay soil that is predominant on this side of town.  Organic matter will also improve sandy soil.  In fact, when in doubt, add organic material: Compost, mulches, manures, worm castings etc, are all good, just be careful with the richer manures, such as chicken poo which should be aged first or it will burn delicate roots.  Chickens and bunnies are far more useful pets than cats & dogs as they will help turn many garden & kitchen wastes into manures that are useful rather than a disposal problem like cat & dog droppings.

3. Likes, dislikes & habits: A major consideration when deciding what to plant is to think about what you and your family like to eat and how you like to cook: Don’t plant a heap of apple trees if you are not into apples.  Don’t select summer-fruiting raspberries if you spend summer up the coast: select autumn fruiting varieties instead. –and don’t let the apricot tree become huge if you are not into bottling and preserving and only need enough to east fresh: Prune it back hard and make room for a few other trees that are also kept small. Remember: you are trying to produce variety across the year, not a huge pile of one thing that ripens all at once. –That’s for commercial orchards.

Are you into Thai food? Then find space for a kaffir lime tree. –or do you envisage yourself sitting in the shade of your backyard food-forest during the summer heat, sipping on an icy gin & tonic? –then plant a Tahitian lime instead.  Don’t forget to allow for new treats as well: If you’ve never eaten a home-grown white peach dripping with luscious juiciness before, then you have never really eaten a peach!  -nothing like the cardboard stone fruit from supermarkets 

Making the most of the space you’ve got

Most gardening books and plant labels give advice on spacing and pruning based on what commercial orchards do, but commercial orchards have to leave space to drive a tractor between trees and to ensure that the whole crop is ripe for picking on the same day.  In a home garden, it’s actually better if the fruit at the top of the tree ripens first, so your harvest is spread over a longer period.  –and so what if the trees grow together into one big tangle?  It just makes it harder for the birds to find the fruit.  Plant trees closer together; at about 2-3m between trunks for larger trees, and then use all the space in between and underneath for many other smaller fruiting plants.  Many gardening books will give you some idea about pruning but we require some new rules for this type of garden: as well pruning to allow light access and air movement, there are new rules such as : Prune off that twig that  might  take someone’s eye out, cut off the branches that get in the way of the trampoline and definitely tie back that  lemon tree that keeps poking you in the bum when you are trying to pick some parsley! Cover walls, fences and established trees with grapes, kiwi vines, passionfruit and espaliered trees.  Squeeze in a tamarillo here and a feijoa there.  Cover the ground with strawberry plants and shove a cape gooseberry where the sun don’t shine (as much). Use the ‘food forest’ method to fill every possible niche with edibles; fruit, vegetables and herbs.        

Feeding

Established fruit trees should be fed each season with good quality compost, aged manures such as sheep, horse & cow poo, and bird manure in moderation.   Feed at the drip line, where the feeder roots are active and keep organic matter clear of the trunk.  Skip feed in winter as deciduous trees will be dormant and evergreens, such as citrus will tend to sprout new lush growth prone to frost damage.

Pruning

Pruning is traditionally done in winter, but here in Australia, our main pruning should be done in late summer to reduce rampant warm season growth and redirect the trees energy into next year’s fruit instead of lots of inedible leafy growth. Cut back anything above reach-height to an outward facing bud, thin out any growth towards the centre and then prune according to tree type.

Apples & pears are pruned to maintain fruiting spurs; Peaches to encourage one year old wood for next year’s fruit and Plums are pruned to maintain cluster buds and one year old fruit.

Winter pruning involves the ‘Three D’s’: Removing, Dead, Diseased and Damaged wood and any major shaping, especially of younger trees.

A year of organic pest and disease control for Fruit trees

Pear & Cherry Slug (also on plums): Dust the tree liberally with sifted wood ash or brickies lime. If you can’t get these, flour is fairly effective if the problem is urgent.

Codling moth (apples, quince and sometimes pears): Wrap a piece if corrugated cardboard around the tree trunk and dispose of it weekly over spring and summer.

Curly leaf (peaches and nectarines) Spray after leaf-fall and again just before budburst. Spray with a copper-based spray if curly leaf has been a problem or with 1Tbsp sodium bicarbonate per litre of water if there has been little or no curly leaf.

Winter: Mix brickies lime (not garden lime) and water to the consistency of paint. Paint all trunks to about 500mm high. This will prevent fungal diseases form being splashed on the trees when rain hits the soil. Spray the rest of each tree (except peaches and nectarines) with white oil to kill any over-wintering bugs and their larvae.  Wear rubber gloves and eye protection while mixing and applying.

Citrus Pests and Diseases: The best defence against pest or disease attacks on any citrus is a well fed and watered tree. When this is done, disease rarely gets extensive enough to effect fruiting and insect pests just become part of your backyard ecosystem: eating and being eaten and doing no more than cosmetic damage to your tree.  If you notice a problem, act; don’t overreact.

Common Problems and Solutions

Citrus Gall wasp:  Caused by tiny wasps laying their eggs beneath the bark. As the larvae hatch and grow, part of the branch becomes swollen and disfigured. As the wood protects the larvae from any sprays (organic or conventional), the only option is to cut off the affected area and dispose of it. The wood must be binned or burnt as composting will allow the wasps to continue to hatch. If there are tiny pinholes in the branch, you are too late as the wasps have hatched.

Yellowing of leaves:  This is usually a result of nutrient deficiencies. While you can search books and the internet for specific needs, it is better to just apply Trace Elements as this will cover all your bases and avoid misdiagnosis. For a quicker result, apply the mixture as per the pack but as a foliar spray, allowing the excess to drip down to the soil. Note that in winter, it is normal for some older leaves to yellow and drop off.

Scale: These are small encrustations on the branches and sometimes on leaves. Most look like brown, black, white or red shields but some varieties are fluffy white.  One simple solution: Apply White Oil.

Ants:  Ants are not a problem, they are a symptom: They are usually only there to feed off the sugary secretions of scale or aphids. Remove the scale and the ants will leave also.  Think of them as a warning system.

Sooty Mould:  This is caused by the sugary excrement of scale growing mould. Check for scale and treat. Open up the tree with a bit of pruning for better air circulation. Spray the leaves with a solution of one tablespoon of ‘Carb soda’ (sodium bicarbonate) per litre of water.  This will temporarily make the pH of the leaf surface unsuitable for the mould to grow.

Brown leaf edges: Salt burn caused by artificial fertiliser, salty bore water or using grey water with high-salt products such as most fabric softeners. Flush well with clean water and check drainage is adequate.

Rotting, black and wilted leaves: Poor drainage or frost damage.  Check drainage, mulch with Casuarina leaves for silica and cover on frosty nights.

Sucking & piercing bugs: Don’t bother too much unless they are actually doing damage. If they are, White Oil them.

Holes chewed in leaves: Usually Citrus Butterfly caterpillars.  In the unlikely event that there are lots, pick them off. Otherwise leave them alone: The butterflies are really pretty and worth a few holes.

Silvery squiggles in leaf surface:  Citrus Leaf Miner; White Oil.

Fruit spotting: Various colours and causes some nutrient-based but most are caused by various citrus mites or fungal diseases. Feed the tree well and spray with White Oil that has a tablespoon of carb soda added per litre of spray.

Fruit distortion and cracking: Caused by fungal disease: Carb soda and Trace Elements.

Thick skin: Can be viral but is usually a copper deficiency. Trace elements and feeding.