By Kim Cantrell and John Rettmann
Hope you all are enjoying this beautiful spring. As the trees are budding out, the blossoms have been nothing short of gorgeous, and the early pollinators are at work.
Let’s continue forth with talking about pruning; this time, we are getting specific in our endeavor. In the first two articles on pruning basics, we covered the fundamentals for pruning most shrubs and trees. For part three, the focus is on the care and pruning of fruit trees, in particular steps you can take to avoid damaging your apple trees with excessive or inappropriate pruning, and steps to take if damage has already been done.
Fruit trees have different requirements and considerations, especially if your goal is a productive tree with lots of wonderful home-grown fruit. I’m delighted to share the advice and expertise of Kim & Company’s and Little Bird Gardens’ expert on pruning fruit trees, John Rettmann. John has a deep love of trees and has been increasing his knowledge, understanding, and techniques for many years. He is a valued member of my team and I guarantee you will hear his name in the gardening world for years to come.
Your apple tree told me to tell you … that you’ve killed it. Well, it’s only a matter of time. Her trunk is rotting, branches splitting, and water sprouts are reaching skyward as a hopeless effort to escape your once-in-a-blue-moon hack job. She’s turning 92 years old this spring, and even though she grew tall and strong in her first 50 years, for some reason people nowadays say she’s too big.
Trees are ruined by a one-two punch. A harsh pruning, followed by years of nothing. Pruning hard can doom a tree, but the sad thing is, abused trees cause their own demise. Only strategic, skilled pruning can reverse the damage. Here’s how to save it.
To begin, you need to know what your tree wants. Left to its own devices, a tree has two goals: reach mature size, as determined by the genetics of her roots, and develop a structure for fruit-bearing branches. Trees can’t bear fruit on first-year growth. Apples, for instance, only really start to bear fruit on third-year wood. Old wood also becomes less fruitful. Fruit spurs age, and new growth often shades out the interior of a tree.
This natural progression gets disrupted by pruning. Good pruning helps maintain airflow and young branching on the entire tree. It helps the tree fight off diseases, prevents limb breakage, and increases yield. Not to mention, it makes the tree more beautiful, because the interior branches are visible, the tree is balanced, and the wood and leaves are healthy.
If your tree has been improperly pruned, I recommend you find a tree rehabber. Not just someone who cuts trees a lot, but someone who knows what anthracnose is (a common fungal disease), who can identify a fruit spur, or count the years of growth since the last pruning.
In the late winter, when there isn’t risk of a hard freeze, have the pruner come and cut out the worst large limbs. This should be fewer than 6 cuts, to begin to untangle the canopy of the tree, and will allow for easier summer pruning. Ask the pruner when they need to come next. If your tree is struggling, they may want to wait a whole year, or they may be anxious to come for a summer pruning, to start suppressing growth. One way or another, your tree should be pruned again within the next 14 months. And mind you, rehabbing a tree takes at least three years.
When your pruner comes for the second visit, they will continue thinning out your tree. If the tree’s pruning budget allows, they will also start shaping fruit-bearing branches. Water sprouts may still remain, but you need to understand that, for fruit trees, water sprouts are a bad habit, and like bad habits, we have to first develop healthy habits before we can totally quit. Cutting all of the “offensive” branches off at once will cause the tree to either fail or fight back harder than before. Most trees allow for no more than 30% of the healthy branching to be removed in one year; this is your pruning budget and includes water sprouts.
This third phase is when the fun begins. The tree should finally start to look balanced and should no longer be producing water sprouts. At this point, the pruner should not have to make more than one or two major cuts per year. Fruitfulness will start to increase. Old wounds are healing. Your pruner should now be able to prune your tree very quickly, not even needing to remove the full pruning allowance to maintain the tree. If you’d like to learn how to trim the tree yourself, ask your pruner to show you.
As the guardian of your apple tree, remember:
1. Let the tree be the size and shape it was designed to be. You can buy trees grafted on dwarfing root stocks. These will be of a smaller mature size. Each species, and even different varieties, have different growth habits. Apples prefer to have a central leading branch and do well with lots of well-developed side branching.
2. Don’t do anything drastic. Make incremental changes year after year. If your tree was already planted before you got there and it’s too big, you have 3 options: cut it down; hire an expert to shrink it down, and maintain it every summer; or change your expectations! Consider that these trees can live for centuries if they aren’t compromised. They are beautiful monuments of the natural history of our Island and can enrich the lives of our future generations if we protect them.
3. Prune at the right time. Most people believe that spring is the best time for pruning. That depends on what the tree needs. Different goals require specific timing, and different seasons demand different methods.
If you are trying to prevent or cure disease issues, pruning must be done during the dry season. If you are trying to reduce vigor or height, pruning is most effective in the mid to late summer when the trees put energy into fruit instead of growth. If you need to remove a large branch, pruning is the least stressful on a tree in the late winter. Spring pruning actually triggers the strongest response from the tree because it is just waking up from winter and has ample time and resources for growth.
Apple trees can have long, beautiful lives if we let them. We can ruin these treasures by combining harsh pruning and periods of neglect. We can restore these treasures through understanding and consistent care. If you want to learn more about the pruning and care of fruit trees, Vashon is very fortunate to have an excellent resource in the Vashon Island Fruit Club. They host regular pruning workshops and demonstrations. You can learn more at vashonislandfruitclub.org.
