Effective approaches to pruning trees, vines and shrubs vary quite widely. There is by no means a “correct” way to prune. And yet, there are some principles of plant growth that help the person with the pruning shears, loppers or saw in hand decide which decisions to make based on acute observations of the tree or vine’s growth.
Pruning is primarily an art of observation, secondarily, of cutting. To prune effectively is to observe what you see and imagine how the plant in question might grow from the remaining active buds or branches, once you have cut, trimmed and, yes, sometimes even hacked away at it.
A fruit tree or vine will grow and produce fruit whether or not you prune it. Nature has a will to live and reproduce, and these beloved plants are no exception. Still, pruning is recommended for optimal plant growth, productivity, disease resistance and aesthetic quality.
Often, the general pruning needs of entire plant families can be grouped together, however each species of plant has a different growth pattern, which demands special attention.
Pruning a deciduous fruit tree or vine when it is dormant stimulates new growth. Pruning a deciduous fruit tree or vine when it is in vegetative or leaf mode, on the other hand, takes away vigor and discourages growth.
When you cut back a tree or vine during its dormancy, the weather is usually colder. These plants have adapted to lose their leaves and store energy in their roots and central trunk or stem during the winter. When you cut them back at this time of year, they are forced to send the stored energy to the points of growth to which you have cut them back when the soil warms up in the spring, spurring rank and vigorous growth. Winter pruning is ideally suited for young trees.
Removing a significant amount of wood or vine – as high as 40+% of the total fruit tree and 90+% of a vine – will drive the formation of vigorous new shoots and first-year branches. This does not necessarily mean more fruit will be produced. Some trees and berries fruit on first-year wood, others on second-year, some on a combination of both, and others still (ex. apples, pears, quince) on specialized nodes called fruit spurs. This is an important element to understand when “pruning for fruit.”
Prune young trees and vines (first 1-5 years) hard during dormancy, removing 40+% of the growth, in order to stimulate branching and new growth.
When you cut a tree or vine back during its vegetative cycle – which normally peaks in the summertime – you are removing energy that is feeding the roots and other parts of the plant through photosynthesis. Summer pruning is one of the most effective methods of controlling large, mature trees and vines whose vigor has gotten out of control.
Prune mature trees (5-15+ years) aggressively during the summer for height control and fruitfulness. Summer pruning can often coincide with the fruit harvest on a large tree or established vine. When harvesting from a large fruit tree or berry patch in the summer, take your pruning tools along and cut back the plant as you harvest, accomplishing two tasks at the same time!
Tip: When you prune a tree or vine, regardless of season, cut back to a node whose orientation you like. For example, if you would like for a tree to open up into more of a “goblet shape,” consider cutting back to buds that face away from the center of the tree.
For more information on winter pruning, please see our article entitled "Winter Pruning Tips."