How To Rejuvenate Your Old Apple Tree With Pruning
Do you have an old apple tree in the backyard? Now is a great time to rejuvenate it!
Prune In Late Winter
Late winter is the best time to prune for several reasons: First, the tree is dormant and will suffer less shock.
Second, pruning in late winter minimizes the exposure of wounded tissues to the ravages of winter.
Third, diseases are less active in winter and you are less likely to spread diseases on your pruning tools. Wound dressings are not needed when pruning in the dormant season.
This will make the tree easier to manage and the apples easier to harvest. Old trees can be pruned into an umbrella shape, with branches cascading in all directions from the main trunk, not allowing tree height to exceed about 12 feet (see the photo above of an old orchard).
Develop A Strong Framework
The most vigorous branches will have glossy bark (not old, scaly bark).
Trim just above these vigorous, sturdy branches. This will bring the tree down to size (see the BEFORE/AFTER figure below).
We want to keep sturdy, productive branches. these will have an angle of 60-degrees from the trunk. To say it another way, using the face of a clock as our guide, the strongest, most productive branches will be at angles of 2 and 10 o’clock.
Remove vertical and horizontal branches. Vertical branches are not fruitful and their narrow crotches are weak. Horizontal branches struggle to support a heavy fruit load.
We want to get more sunlight and air movement in the tree. This will improve fruit color and reduce humidity that promotes diseases in the canopy.
Start by removing the water sprouts. These are vertical, pencil-thick shoots. Water sprouts are unproductive and clutter up the canopy.
Remove broken branches, branches that rub one another, and inward facing branches.
To avoid sunscald damage and shocking the tree, avoid removing more than 25 percent of the tree’s wood at any one time. It’s best to give yourself at least two years to rejuvenate the tree.
Apple trees age like people do. They can live to be 100 years, but they reach their prime at around 25 years. Pruning an old tree will lead to higher yields and much better quality fruit, but your tree is still old. It’s nice to have a tree with character and charm in the backyard, but it doesn’t hurt to have a young and productive tree nearby. Spring is the best season for planting.
Written by Tom Kalb, Extension Horticulturist, North Dakota State University. Photo courtesy of Mark Shirley.