Why is it now suggested to prune Apricots in the fall rather than the winter? If this is correct, will it be too late to prune in January?
Conventional thinking has changed concerning the pruning of Apricot trees as well as other deciduous fruit trees.
Pruning in the fall always raises the question about dormancy. The winter months don't signal the beginning of the dormant season. It begins much earlier.
Dormancy is defined as that period when a plant is not actively growing. Evergreen landscape plants are dormant throughout the year when they are in bud and bloom. With fruit trees, dormancy begins in the late summer not when the leaves drop off, and the temperatures turn cool. The exception is those varieties with a maturing crop. It’s now suggested to prune deciduous fruit trees in the late fall or early winter besides January and February.
With apricots, the fall pruning is highly recommended to avoid Eutypa Die Back. Eutypa Die Back is an airborne organism that infects the trees through the pruning wounds when conditions are cool and damp. It affects only apricot trees. The disease causes a sudden die back in the canopy, but it doesn’t show up until after Memorial Day. At this time, there is a sudden die back in the canopy for no apparent reason.
The pruning wounds or entry points seal themselves or callus over naturally in seven to ten days depending on the temperature. The application of a pruning paint or seal doesn’t adequately protect the open cuts when conditions are damp.
There are windows of opportunities to prune apricots during the winter, but they vary yearly. It was tough last year because of the rain, but not a problem the previous two years. With the late summer and fall, you avoid these concerns, as the conditions are much warmer and drier.
Phytophthora Root Rot causes similar damage as Eutypa Die Back on apricot trees. Phytophthora occurs in the spring of the year when limbs, branches, and twigs fail to leaf out or collapse after breaking dormancy. The dieback can be a progressive occurrence over several years.
Phytophthora Root Rot is a disease that attacks the roots of many plants and is caused primarily by excessive summer moisture.An established apricot tree doesn’t require frequent watering.
They thrive nicely when deeply watered twice a month after the rainy season stops. Also, the area under its canopy should be left unplanted. This also applies to Cherries, Peaches, Nectarines, and Plums. After Labor Day, stop or reduce the watering as it’s not necessary. The stressed tree(s) is then susceptible to borers. The cumulative effect is that the tree eventually dies.
You can conceivably have both problems, Eutypa Die Back and Phytophthora Root Rot, in any given year. While it’s not a concern with other fruit trees,
I’d check the five to seven-day forecast before pruning apricots. It isn’t the end of the world if the tree isn’t pruned this winter because of the weather.