Submitted by Calvin Finch, Ph.D., Manager, Conservation Division, Water Resources & Conservation Department, SAWS, and Horticulturist

FEBRUARY IS PRUNING MONTH

February is pruning month. Today I am going to try and describe several types of pruning. For those of you who do better with diagrams than words, visit plantanswers.com for illustrations on pruning.

 

We prune peaches and plums to an open vase shape.

 

·        The first thing to do is cut all suckers (stems originating from the roots) off at ground level. Suckers are stems of the rootstock. If suckers are allowed to grow they will overcome the top of the tree and, in most cases, you will have an unproductive tree. The top of the tree (scion) is selected for fruit quality. It is grafted on a rootstock selected for toughness.

 

·        Secondly, cut out all dead, diseased, and injured stems.

 

·        Next, identify and cut out any water sprouts. Water sprouts are branches growing straight up from horizontal scaffold branches. They are branches that have few buds and grew at an extraordinary rate in the last year. Water sprouts do not produce much fruit and will grow above the main part of the tree if you let them persist.

 

·        Now that you have cut out all the suckers, dead wood, and water sprouts begin cutting out stems that grow off the main scaffolds into the middle of the tree. Look at the tree as a thick-sided wineglass. The middle part should be open to allow light and air to penetrate. The bowl of the wineglass should be about 18 inches thick and reach out at 60 degrees from the trunk.

 

·        Don’t worry about the small stems that cover the inside of the wineglass bowl. When they leaf out they shade the main branches to reduce sunscald and some will have blooms and fruit. In the “old days” some pruners preferred clean middles to the trashy middles that we now recommend.

·        To control size use thinning cuts, identify the tallest (often called the offending branch) and follow it back to its origin where you cut it. Keep cutting back the offending branches in this manner all around the tree and you reduce height without disrupting the growth habit of the tree.

 

Peach trees are pruned to limit the size of the crop to that which the tree can support and to open it up to light. Fruit will not color properly without light and fungus prospers in the shade. The open peach tree is also easier to spray to prevent insects and diseases.

            There are three basic pruning tools. A pruner is a tool that resembles scissors. It is used to cut small branches under a half-inch in diameter. Loppers are used for cutting branches one-inch or less. The third necessary tool is a pruning saw. My favorite is made by Felco. It has an eight-inch blade that folds into a plastic handle much like a pocketknife. Use it to cut one- to four-inch branches.

If your trees are tall it may be necessary to have a pruner on a pole and/or a pole saw. Your favorite nursery, horticultural supply store, and home improvement stores all carry pruning tools. Buy medium grade or high quality tools. They are safer, keep their sharpness longer, and are easier to use.

            A second common type of pruning that should be done now is pruning to revitalize a shrub. Without pruning, shrubs like ceniza, pomegranate, crepe myrtle, viburnum, vitex, and many more will become thickets of bare stems. Every year remove a few of the oldest stems at ground level to open up the plant. Loppers and/or the pruning saw are needed for this job.

Modern roses do best if they are pruned every year. Prune hybrid tea roses in late February. The process is very similar to peaches. The stems that originate below the graft are removed. Take out all diseased and dead wood and then open up the middle. Select a height based on the vigor of the plant. Thirty inches tall is a good average height.