Whether apple, fig, plum, or citrus, fruiting trees are extremely attractive, versatile, and productive, able to produce fruit for at least thirty years or more. They can, however, be susceptible to numerous fungal diseases with the potential to ruin your orchard. By maintaining strong, healthy trees and keeping an eye out for signs of the most common diseases, you can ensure a thriving, disease-free orchard and a bountiful harvest.
Apple and pear scab
Scab is one of the most common fungal diseases that affects apple and pear trees. It appears as leaf spots, which get bigger and darker over time, as well as scabby patches on the fruit (which is, however, still perfectly edible when peeled). Leaves infected with scabs also typically shrivel and drop by mid-summer. If your trees develop scabs, ideally, you should clear away the fallen leaves as these can encourage reinfection the next year. And, since scab flourishes in humid conditions, improving air circulation around your trees can help your trees dry out faster following rainfall and therefore prevent the disease. Ensure your trees are spaced far enough apart and pruned to encourage maximum air circulation.
Fungal rust is a common problem for fruit trees, particularly apple trees. This disease is spread via fungal spores that grow on plant debris. When it infects fruit trees, rust results in yellow spots on the leaves, and usually causes them to drop from branches prematurely. Although rust usually doesn’t kill the tree, it does weaken it and therefore increases the risk of infection from other diseases. If you notice rust on your fruit trees, you need to prune all infected leaves and fruit as soon as possible. It’s also essential to burn or otherwise get rid of the leaves far away from the orchard to stop the rust from spreading. Applying a fungicide can be particularly beneficial if rust fungus is a significant problem in your local area; be sure to do so in the spring before the rust has a chance to start producing spores.
Silverleaf disease is mainly a problem with plum trees, but it can also affect apple, cherry, almond, and apricot trees. It’s a fungal disease that causes the leaves to develop a silver sheen and the branches to eventually die. Fortunately, mild infections will clear on their own, as long as all infected parts are pruned away and destroyed. If, on the other hand, the trunk is also infected, the whole tree needs to be dug up. Regular pruning is key to keeping silverleaf at bay — pruning should ideally be done during dry periods, and at least a full 24 hours after any rainfall to minimize risk of infection.
Although it takes some time and effort, there’s nothing more rewarding than a great fruit harvest. By taking good care of your fruit trees and working to prevent common fungal diseases, you can ensure your orchard thrives for years to come.