The Dirt Gardener's Column for January 16

Q. My four-year-old Apricot tree has grown very large. When is the best time of the year to prune it and how much should I cut it back?

A. Contrary to most gardening books, an apricot tree is best pruned in the fall. A fungal disease called Eutypa causes an unexplained die back during the summer months. This air-borne disease enters a tree through the new pruning wounds that haven’t callused over during rainy periods, During the winter, Apricots can be pruned when there is a two to three week period of dry weather. About a quarter of the growth is removed each year. You prune out enough branches to evenly shape the tree selecting old wood whenever possible. You also thin out those branches that are to close to one another. This spacing allows sunlight to evenly penetrate all parts of the fruit-producing top. The majority of the fruit is borne on one-year old or last years wood. The outside branches of apricots have a tendency to lower each year with the weight of the fruit and foliage. They maybe cut off the tree without damaging the tree. These branches will be replaced with new ones from the inside growth. Apricot wood is brittle, so care should be taken not to let the branches spread laterally to great a distance. I’d select branches with an erect growth habit when possible. A sturdy framework is desired even at the expense of fruit production. There are a number of pruning books available at your favorite garden center that you can use as reference. Better yet, check to see when the pruning demonstrations are scheduled.

Q. I’ve planted three bare root grape vines behind my home and they’re doing great. Since I know nothing about caring for grapes, I borrowed a book. Unfortunately, the comprehensive instructions just confused me. So, how do I proceed?

A. Pruning grapevines can be very confusing. I’ve found that many of the “How To” pruning books just don’t simplify the process. What the books fail to give is a definite starting point. So, let’s step back and gather our thoughts. Grapevines are very prolific during the growing season. They produce a maze of vegetative leaves and stems going in every which direction. The focus of the first winter’s pruning is to identify the main trunk or in your case trunks. You select the three straightest vertical shoots from the vegetative maze to form the trunks. One from each of the three plants you planted. These trunks are supported by a stake or post of an arbor or some type of trellis. The balance of the basal growth is then cut off. The lateral growth or shoots originating off the trunks is then selected. If you find none, don’t worry, as they will develop next year. Personally, I’d remove all the side shoots now and reselect them next winter. Once the main trunks had been selected, the ‘How To’ pruning books can take you the rest of the way starting next year. And finally, keep in mind that each winter, a significant amount of the vegetative growth produced each year is pruned off.

by Buzz Bertolero, CCNP