Best Time to Prune Apple Trees
in Northern Colorado- Fort Collins, Loveland, Windsor.
What’s the best time to prune apple trees? I’m glad you asked, because I just wrote this article to answer your question. Let’s start with the worst time to prune apple trees: during wet weather. The reason for this is due to a bacterial disease many fruit trees are subject to called Fireblight. Fireblight can enter trees at fresh wound sites such as pruning cuts, and is easily spread by rain drops. So it’s best to avoid pruning during wet weather (not that we have much of that in Colorado anyway). If you have a sprinkler system, be sure to not let it get your fruit tree wet.
OK, back to the original question: best time to prune apple trees. The answer is: it depends on what you want to achieve. I hate “it depends” as an answer, but bear with me. There are different reasons for pruning apple trees, and different seasons for the reason, if you catch my drift. Here are some different reasons for pruning, and when they are best done:
Training: Pruning to improve form or structure.
This is often done while the tree is dormant, and is probably best done in late winter or early spring, so early March for example would be a great time. If the tree has just been planted then doing some training at that time is OK as well. Training a fruit tree for form and structure is about creating strong branches that will support heavy loads of fruit; putting those branches within arm’s reach, and creating a shape that will give leaves and fruit plenty of sunlight, as well as air circulation. Popular forms for apple trees include the Central Leader, where the tree has a strong and straight main trunk, with strong branches coming off the trunk- larger ones on the bottom, smaller branches towards the top. The Modified Central Leader has two or more tiers, or whorls, of branches seperated by about two feet, which allows for good air and light penetration. Then there is the espalier form where the tree is trained along along a single dimension.
Removing dead branches, suckers and crossing branches.
This can really be done just about any time of year (except when rain is forecast), but might be better done in late winter. This includes any dead or diseased branches, suckers and watersprouts (skinny branches growning straight up off the trunk or out of the ground), branches that are rubbing or crossed, and smaller branches that might be in your way; go ahead and prune them out whenever you like.
The “Rejuvenation” prune: Pruning a neglected tree.
Maybe your apple tree has never been pruned, or maybe it’s just been way to long, and now you’re ready to mend your relationship with your tree. Good for you! It’s not too late (but don’t let it happen again). This really needs to be done while the tree is dormant: Late winter is good. Don’t try to get your tree back in shape in just one year: it may take a couple years of pruning to get it back on track because you shouldn’t remove more than 1/3 of the tree in a year. This is the most common pruning request I get.
Thinning fruit for better quality fruit.
The secret to large, sweet and juicy fruit is thinning. OK, genetics, environment and other factors come into play, but thinning the fruit is one of the things we have control over. Thin fruits when they are about the size of a grape: usually sometime in May. Just pluck them off with your fingers, leaving only one fruit every six to eight inches along the branches. Be merciless, and you’ll be rewarded at the end of the season. Thinning will also help break your tree out of an every-other-year cycle, and in apple trees it will reduce worms in the apples. Of course, if your tree is only developing a handful of fruits you won’t need to thin (call me and I can help you figure out why your tree isn’t setting fruit).
Pruning to keep a tree within its space.
Sometimes we want to limit a fruit tree’s growth and keep it small. This can be achieved by pruning in May or June after the new growth has been pushed out; trimming that new growth back hard will help limit the size of the tree. This is because it costs the tree energy to push that new growth out, and by snipping it back before it gets a return on investment, we discourage the tree from sending out more growth. On the other hand, winter pruning will actually encourange a tree to push out more new growth.
I hope that helps answer the question of when is the best time to prune apple trees. You can always call if you have more questions: (970) 690-0769. Thanks for reading.
Photo credit: Muffet / Foter.com / CC BY