Extension folks use the term “home orchard” quite loosely—generally, we are talking about anyone who is not producing fruit on a commercial scale. Per that definition, you might have one or two trees, or you could have several acres of them, and still fall into a “home orchard” producer category. One of the most common issues in home orchards, and the one I’ve gotten the most calls on lately, is disease and insect damage. There are several things home orchard producers can do to help improve their tree health and fruit quality.
The first thing to consider is getting out there for early identification of any issues. Unfortunately, when I get calls in June about fruit with extensive damage, there’s little we can do to save the crop. The best way to reduce insect and disease problems is to get ahead of them via scouting. There are two parts to scouting for pests and diseases- understanding WHEN a pest or disease is likely to be an issue and understanding WHAT that pest or disease is. As an example, a recent orchard I visited was having some insect damage issues. There were a variety of trees, including plum, peach, apple, pear, all at different points in the “fruit set” stage of development, where fruit is present and maturing. The majority of the fruit on the trees had been damaged, exhibiting crescent shaped blemishes and occasionally the presence of an insect larvae in the fruit itself. The culprit was one of the most common pests of fruit trees, the plum curculio beetle. Earlier recognition of this pest may have allowed us to get on an appropriate spray program to reduce losses, as we know the plum curculio typically needs control starting right at petal fall through harvest.
Scouting to identify the problem and then implementing a targeted spray program are the best defense against insect and disease related losses. There are generally four types of spray you will find on the market. I do want to note here that one of the biggest challenges for home orchard folks will be getting adequate coverage of the spray without specialty equipment, especially for larger trees. That is also why we recommend an appropriate pruning program to help keep trees a manageable size (and pruning also reduces pest and disease issues). Dormant spray is applying horticultural oil on trees during the winter or dormant period of growth. This spray is useful for pests on the bark of the tree like aphids, mites, scale insects, and so on. Typically, dormant oils are used once per year. The second type are insecticidal sprays targeted for a specific insect. These sprays kill pests that feed on foliage, bore into the tree, or feed on the fruit. Most fruits need multiple insecticide sprays through the growing season to protect against insect pests. You should not use insecticidal sprays when trees are flowering as they will kill pollinators and beneficial insects. Fungicidal sprays are used to control the spread of fungal and bacterial diseases- again, identification of what fungal or bacterial disease is essential for proper use. Depending on the issue, multiple applications may be needed in a season. Finally, homeowners can use a general-purpose spray. These sprays are used at a regular interval during the growing season and can help control our most common pests and diseases. The major benefit is that the orchard owner does not need any specialized knowledge of plant diseases or insects in order to use these “home orchard sprays”. However, downsides of these products are that they are often a lower concentration than is needed to control some pests, they have to be used more frequently than targeted products, and they increase pesticide exposure.
If you have a pest issue in your home orchard, or if you would like help getting more information on scouting and spray programs, please let us know at uge3181@uga.edu.
