SUMMER FRUIT TIPS
SUMMER IS a great time to be in the orchard, with lovely, long days to admire the ripening crop on your trees. There are a few jobs you can complete under the summer sun that will improve your tree health, reduce tree height and improve the quantity and quality of your crop.
WATERING & FEEDING Water stress, caused by a lack of water, or overwatering followed by underwatering, can cause the developing fruitlets to drop. Keep young trees well watered, providing a good drink at least once each week. Ideally, leave a hose dribbling in the “drip line” of the tree for an hour or so for a deep watering. Apply a thick layer of mulch in a doughnut shape around the base of the tree. It’s important to keep mulch away from the trunk, in particular the bud union on a grafted tree (where the variety is connected to the rootstock) to prevent the bark from rotting. Mulch will provide a layer of insulation for the soil to reduce evaporation of moisture, as well as helping to suppress weeds from growing around the base of the tree. Just like a growing child, fruit trees need a balanced diet. Applying a “side dressing” (sprinkling a granular fertiliser on the ground around the tree) of a specialised fruit tree feed a couple of times through summer will provide the perfect balance of N, P and K. Nitrogen supports the leafy growth of branches, phosphorus promotes tree health and root development, and most importantly (and in the largest ratio), potassium looks after fruit growth earlier in summer and encourages the initiation of buds later in the season for the next crop.
SUMMER PRUNING Summer pruning is one of the best ways to keep fruit trees small. Giving your trees a clip in December, then again in February, will slow down growth. Admittedly, this will also reduce the crop, which is a tough call. You may even prune some of the baby fruits off, but as they say, no pain, no gain. Pruning during summer causes a small amount of stress on the tree, which stunts growth slightly. Also, by removing some leaf coverage, summer pruning reduces the available energy for the tree to use to grow. Successful summer pruning can keep a 10-year-old plum tree to 1.5m tall, compared to 4m-plus if left to grow untended. Best practice is to prune new growth back by half in December, followed by another clip taking half of the subsequent growth in February.
As with all pruning of fruit trees, care needs to be taken to prevent bugs getting in through the wounds. Prune only on a sunny day when there are at least a few fine days forecast ahead. Pruning when rain is forecast is asking for trouble – diseases thrive in warm, wet conditions. Seal all pruning wounds that are thicker than your pinkie finger with a pruning paste like Bacseal. This will prevent diseases entering through the pruning wounds and also helps them heal quicker. Use clean, sharp secateurs, sterilising the blades with methylated spirits or bleach. A permanent part of your pruning kit should be a sprayer bottle of meths and an old rag to wipe the blades. If pruning more than one tree, stop and clean the blades between each tree.
PESTS & DISEASES There are a few bugs and blights that can niggle fruit trees in the warmer months. Keep a close eye on your trees, inspecting the fruit, leaves and bark for signs of pests or diseases. Infestations and infections can develop rapidly, so regular examinations will help catch problems in the early stages. Brown rot on stonefruit is the most common disease and can devastate a crop within days. More common in humid conditions where it thrives, this fungal disease starts as small brown spots on the fruit, quickly spreading to cover the entire skin with powdery, tan-coloured mould and rotting the fruit.
Prevention is best. Copper sprays in winter will suppress disease spores that overwinter on the tree, as will removing any infected “fruit mummies”. Brown rot is most likely to cause problems 2-4 weeks from harvest, when the sugar levels of the fruit are increasing. Applications of Yates Nature’s Way Fungus Spray fungicide during this period, every 10-14 days, is recommended. This product has no withholding period.