Do I need to spray them? If so, when and with what? Do we spray the limbs or the roots of the tree. Thank you for any help you can give. – David H.
I feel your pain and empathize with your frustration over trying to grow an abundance of succulent peaches only to have them fall off the tree and appear rotten inside – the indignity of it all. In many cases it is like the tree is mocking us, knowing that we are getting more and more excited as the peaches become riper and riper with each passing day to then be so disappointed when they fall off and appear to be damaged.
The unfortunate part is that you are growing peaches, which historically have taken quite a bit of care to grow well in the deep South. That is somewhat surprising considering that Georgia is the Peach State and Chilton County and Limestone County have numerous peach orchards that produce very tasty fruit.
With all the interest in edible landscaping and locally grown produce, home orchards are definitely on the rise. There are some fruits that are fairly easy to grow – I would include blueberries and figs in this category – while others demand a good bit of effort on our part to have favorable results. Unfortunately I would include peaches in this category. To have a good crop of peaches each year requires several things, including a good spray program to control insects and diseases that affect the peach tree.
Fruit drops from trees due to one of three causes. The first is a natural occurrence and is usually seen around the end of May or early June in our area. Often you will see numerous small, green, immature peaches littering the ground under your tree.
The tree does this naturally as a thinning mechanism to ensure that enough food will be available to have the necessary seed produced for future growth. If this has not happened naturally, it is a good practice to physically hand-thin young peaches off your tree – space them about six inches apart to ensure good air circulation and sunlight for fruit to grow.
The second reason for fruit drop is environmental conditions. Cool, wet weather in late spring will cause fruit to drop. This does not mean freezing weather but times of high rainfall when the May high temperatures are below normal. Also, it can be due to unseasonably hot weather or an erratic rainfall pattern. The trees would prefer even moisture if they could place an order, but Mother Nature does not often listen.
The third culprit is more of what you are seeing – an insect or disease problem. Peaches are notorious for attracting insects and diseases, and sadly we have to rely on a fairly vigorous spray program to ensure success.
The two biggest problems (but not the only ones) are the plum curculio beetle and brown rot, a fungus. The plum curculio is a snout-nosed beetle that lays its eggs in small slits that the female carves in young fruit. The larvae then feed on the fleshy insides, resulting in you finding a worm (actually a larvae) when fruit is opened.
Brown rot is a fungus that can infect both the outside of the fruit, literally covering all of the stone fruits, grapes, muscadines, etc., with a powdery brown substance. In peaches and nectarines, this fungus can be found growing inside the fruit around the seed. In either case, whether it be the plum curculio or brown rot fungus, once you see the problem it is too late to really control.
Begin by removing all foliage that has fallen to the ground each fall – discard the old mulch and fallen leaves and replace the mulch. Remove any shriveled-up fruit left on the tree – these look like they have been mummified, and they harbor the disease. In January and February I would spray the trees with dormant oil (to control overwintering beetles) and lime sulfur (to help with fungal spores). Spray the lime sulfur on the tree and on the soil. It probably is too late to do this year but put it on the list for next year.
Prune out any dead or damaged tree branches and stems, and thin out branches in the center of the tree to expose the foliage to more sunlight. Fertilize with a good, slow-release fertilizer in mid-April as trees begin to grow. I like to use organic fertilizers, and adding compost as your mulch will definitely help. Fertilize again, especially if using an organic source, after harvest in late July.
Next you will begin a spray program and the easiest way is to use one of the many multipurpose fruit tree sprays sold by one of the pesticide companies. They have an insecticide and a fungicide present, and they are labeled for fruits. Follow the label directions exactly as to when to spray, the amount and how often; this is very important. The first spraying is just around the corner as flower buds begin to break, so get ready and watch your tree for the signals.
Lastly, there are some great resources available from the Extension Systems, whether it be Georgia, Alabama or Mississippi. Our Alabama Cooperative Extension System (www.aces.edu) has two good publications – #1308 IPM for Home Orchards and #1182 Brown Rot of Stone Fruits; both of these are worth downloading.
Things to do right now:
Rejuvenation pruning (severe cutting back) of holly and crape myrtle needs to be done before new growth begins.
Cut back ornamental grasses to 12 inches tall; new grass blades will come out from the older shoots. You can also divide the grasses at this time.
Consider reducing the size of your lawn; this will lessen your weekly maintenance chores and minimize water use during the summer.
Harvey Cotten is the chief horticulturist and vice president at the Huntsville Botanical Garden. Write c/o The Huntsville Times, P.O. Box 1487, West Station, Huntsville 35807.