It's Winter - Now What?
Post sponsored by Welcome to PDX Real Estate Agent, Deb
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Post sponsored by Welcome to PDX Real Estate Agent, Deb 〰️
Winter Pruning Guide
Welcome to winter! The days are shorter, darker and colder. Your fruit trees have shed their leaves as a result of the shorter days. They can sense these changes due to their photoreceptors picking up less sunlight. Trees are ancient and intelligent, using a feedback loop of hormones to signal when and how to prepare for the long sleep. The higher presence of the hormone abscisic acid lets the tree know it is time to sequester water, sugars and seal off openings from fallen leaves. Due to the trees being in a state of rest, it is considered the ideal time to make some of the big structural changes you may have been considering.
Saving your larger cuts for the winter means you will not be cutting off any major parts the tree is using to produce sugars and transport water while the tree is actively growing. It is important to note that winter pruning is stimulating. When the tree wakes back up there will be vigorous growth in response to cuts made in the winter. Therefore, if you’ve made a few pretty large cuts it will be important to get back out there in the summer.
When to prune
January - March is the window for winter pruning. Do not prune in below freezing temperatures.
Who to prune
Fruit trees can suffer from different pests, diseases and have different growth habits which is always important to note in how we care for them. In the PNW, it is strongly advised to NOT prune any stone fruit in the winter. A stone fruit is any fruit that contains a pit in the center. Our winters are extremely wet and most stonefruit is very susceptible to fungal issues and bacterial canker. We reserve the winter saw for our apples, pears, quince, and figs. You can prune persimmons during this time but they are pretty weak wooded and good about “self pruning”.
What you will need
A very sharp saw, very sharp loppers and very sharp bypass pruners. Do not hesitate to size up your tool if the cut is not easy to make.
What to prune
First, get rid of anything dead, diseased, or dying. Technically you can remove these things at any time of year. Next, I typically prioritize height and then opening up the center by getting rid of branches growing towards the center. If there are any branches reaching the ground those should also be removed. If the tree is still a bit cluttered after addressing all of the above then I would suggest prioritizing crossing branches, branches facing down, branches that are very close to each other, or branches that don’t look like they will be strong enough to support fruit weight.
How to prune
There are a few pruning cut phrases to know.
A heading cut: a cut to a bud or fruit spur. (Reserved for summer as it’s typically used on thinner newish growth)
2. A re-leadering cut: a cut that removes a branch to another branch that is at least ⅓ of the diameter of the branch being removed.
3. A thinning cut: a cut that completely removes a branch/twig.
4. Three-point cut: This is where an undercut is made ⅓ of the way through the branch (either literally under the branch or in the direction the branch will likely fall), then another cut is made just outside that cut all the way through the branch. Once the branch begins to give it will hitch at the undercut made. Remove the sawed off branch from the tree and begin to make your actual cut just outside the branch collar.
In all cuts made to the tree it is extremely important to be aware of the branch bark collar and to not cut into it! This is a wrinkle where a branch typically meets a main scaffolding branch, a main lateral or the trunk of the tree. The branch bark collar has hormones that allow the tree to compartmentalize the wound being created. Trees do not heal, technically they seal off. Working with your tree by knowing a bit of basic anatomy and physiology goes a long way in maintaining the health and longevity of your tree. When you are going in to make a cut, aim to create the smallest diameter wound possible while getting as close to the branch collar as you can without cutting into it. It is not necessary to use any paints to seal off the wound. Trees are ancient and intelligent.
How much to prune?
Keep in mind that it is suggested to only prune at or below a budget of 30% of the tree canopy for the entire year. This is to prevent shock and extreme response growth.
Why prune?
It is important to maintain a consistent pruning schedule to ensure the canopy stays open to allow airflow/sunlight through, the height of your tree remains accessible for harvests, the tree can support the weight of fruit and continuous removal of anything dead or diseased asap.
Sanitize, Sanitize, Sanitize
If you have multiple trees, sanitizing between trees is imperative. We use 70% isopropyl alcohol on our tools. This ensures you will not be spreading any potential diseases between your trees.
Pest Management
All of these things combined help with pest management, the health of the tree and improving the quality of your fruit. Alright, you’re feeling good about the strategic well placed cuts you’ve made this winter. The next thing to be aware of is orchard sanitation. In any other context, leaving the leaves is so important for so many different critters visible and invisible. For our fruit trees, picking up any leaves, wood or fruit and discarding them is key to integrated pest management practices. This is because a lot of common pests overwinter within fruit tree debris.
Okay, you’ve made it to the end. I hope you feel confident and ready to take on your fruit trees. However, if you still have questions or don’t have much time to set aside for your trees, we got you!
Do you have questions or need help?
Check out the Home Orchard Education Center for workshops and more
Find articles and more with the Oregon State University Extension school
Take the next step with Portland Fruit Tree Project!
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