This post is in response to this question, “is it too late to prune fruit trees”. In South Coastal BC fruit trees can be safely pruned almost any time from late January through to the end of September. The only time during these months when you should not prune is when it is raining. During the rest of the year, October through mid January, the risk of disease infection is too high for pruning.
The disease danger from October through mid January is due to the cool wet weather, ideal for disease spread, and that the trees are dormant and unable to heal pruning wounds. During warm dry weather in the spring and summer the disease do not spread as they do duding cool wet weather and they are able to heal small pruning wounds.
The traditional approach to pruning fruit trees in BC was to only prune during the winter or dormant season. When summer pruning was introduced into commercial orchards it was to remove shade that was preventing apple coloring before harvest. Today various types of summer pruning are used almost exclusively to maintain espalier fruit trees and to slow the growth of out of control trees. Summer pruning is also the primary technique used to shift tree growth from vegetative to fruit production.
Most summer fruit tree pruning in Coastal British Columbia is done during the months of June, July and August. I will post details of the most commonly used techniques during those months.