Now is the right time for fruit growers in Arkansas to prune their fruit trees, said Shaun Francis, Extension horticulture specialist for the University of Arkansas at Pine Bluff.
The process, which should be undertaken annually in the late winter or early spring, will help ensure higher yields and better tasting fruit when harvested, he said.
“Pruning allows fruit growers to direct the growth of a tree into an optimal shape and form,” he said. “In addition to ensuring higher-quality fruit earlier in the season, pruning also allows fruit trees to live significantly longer.”
Francis said pruning alleviates overcrowding and increases the amount of available sunlight and air circulation throughout the tree. While sunlight speeds up fruit set and increases fruit flavor and quality, adequate air circulation properly dries out the tree and reduces the potential for disease infection. Pruning also allows the fruit grower to remove undesirable wood that hinders fruit growth such as dead, diseased or broken limbs.
“Growers should prune their trees during the late winter or very early spring while the trees are still dormant,” he said. “Not only is it easier to identify undesirable branches when the trees have no leaves, but winter pruning also enables the pruning wounds to heal quickly when the trees start to grow.”
Francis warns that pruning should not be undertaken too early in the winter season, as recurring low temperatures can cause damage to pruned trees. Late spring and early summer pruning should also be avoided as conditions are optimum for disease organisms that can invade pruning wounds.
Before pruning, growers should have access to the pruning tools necessary to make sharp cuts in their trees. For small-scale or home fruit growers, hand-held tools such as hand shears, lopping shears, pole pruners and pruning saws work well and are the most economical options.
To start pruning, growers should remove all dead, damaged or diseased wood on their trees, including broken branches. Branches growing straight upright should also be removed as these will remain vegetative and will not produce fruit. Branches that point downward (beyond 90 degrees) are usually weak and unfruitful or they produce only small fruit. These too should be removed.
“Remove branches occurring within the first two to three feet above the soil on the main trunk, as this allows growers to more easily conduct management practices under the tree,” Francis said. “It is important not to leave stubs when pruning these branches.”
When horizontal cuts are required, they should be made at an angle, he said. The angled cut prevents water from setting on the surface of the pruning wound, thus reducing the potential for rot and infiltration of diseases or pests. Dipping the blade of a pruning tool into a disinfectant solution before moving on to the next tree is also an effective disease prevention practice.
Next, the tree canopy should be thinned. Remove any branches growing toward the center of the tree, as well as branches that crisscross each other. Crossing branches rub against one other and cause bruising of the bark, creating an entry point for insects and disease.
“Remove branches that are set at very narrow or wide angles in relation to the center of the tree,” Francis said. “Fruit on branches with narrower angles is often too high to be picked, while branches with wider angles often break when laden with fruit. Prune back branches until there is about 6 to 12 inches of air space around each branch.”
Next, the main branches of the trees should be cut back to a height from which the fruit can be picked without the use of a ladder. This practice encourages branches to grow shorter and sturdier, enabling them to better support the weight of the fruit. As a rule of thumb, it is best to remove around 30 percent of the previous year’s branch growth.
“When fruit trees have been neglected for a number of years, they become overgrown with too many branches,” Francis said. “Although the amount of pruning needed to correct this may be substantial, it should be done over a period of three to four years to avoid the consequences of over-pruning.”
Once pruning is complete, the pruned shoots and branches should be discarded or placed in a compost heap. Separating the cut plant parts from the growing trees helps prevent the occurrence of dwelling sites for insects and diseases.
Francis said once pruning is complete, growers should remove any debris on their pruning tools with a dry cloth. Soapy water and steel wool can be used to remove any sap that remains on the blades and after drying. Adding a light household or mineral oil to the blades can help keep them sharp for future use.
“Arkansas fruit growers who prune their trees once a year will be able to see the difference the practice makes,” he said. “In addition to ensuring the longevity of their trees, they will be able to enjoy a more bountiful and tastier harvest of fruit.”
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— Will Heheman is a writer/editor for the UAPB School of Agriculture, Fisheries and Human Sciences.