The ink is hardly dry on the last growing season, and here I am talking about getting the fruit trees ready for spring! Seems early, but it’s right on time.
Depending on how many trees you have, and how much help, you might start early in the year with the pome fruits, such as apples and pears. With fewer trees or more help, you can start later, but pruning must be completed by the time the trees start to leaf out. In case you’re wondering, the stone fruits — apricots and cherries — should wait until last because they are more prone to winter injury.
This assumes that you have some trees in the ground. If you don’t, but plan to plant some, there are things to know. You might guess that disease resistance is huge. If you could choose between a variety that has to be sprayed and one that doesn’t, what would you do? Well, you absolutely can choose, and I’ll give you some lists to look up in the next column.
Pruning basics
If you understand the reasons why we prune fruit trees, you can get the best possible results and make good use of your time. It’s all about the fruit! You will want sunlight and air to penetrate the tree so that fruit can ripen, and diseases favored by poor air circulation can be kept at bay. Research has shown that each ripening apple needs the carbohydrate production of about 50 leaves, so you’ll need to keep those as well.
You will typically train those pome fruits to a strong central leader, and the stone fruits to what we call an “open center” or vase shape. Understanding the difference between a “heading” and a “thinning” cut is crucial, as is the skill to make a large cut that will close completely over time.
Dormant oil
You can prevent common diseases by choosing disease-resistant cultivars. If you prefer not to spray, or aren’t likely to stay on top of 10- to 14-day spray intervals, this is for you.
If you had existing trees, and you sprayed only once a year, the material would be dormant oil. This goes on in February or March, before growth begins. It’s a highly refined oil that serves to smother overwintering insects or their eggs. Dormant oil is easy to find, has low toxicity, no residual activity and works at a time of year when beneficial insects are largely absent.
Great resources
Raising tree fruit takes a good bit of commitment, and it’s rewarding. It helps to start with an understanding of what works. Extension has many research-based pointers that can help. A brief pruning guide can be found online at extension.missouri.edu/scott/documents/Ag/Horticulture/Pruning-Fruit-Trees-Shrubs.pdf.
For some hands-on practice, consider attending our fruit tree pruning workshops, scheduled for 2 to 4 p.m. Feb. 16 and 17 in Columbus. These are free, and you can register by calling our office. For more information, see our website at extension.purdue.edu/Bartholomew.
Kris Medic is Purdue Extension Bartholomew County’s educator for agriculture, natural resources and community development. She can be reached at 812-379-1665 or [email protected].
