How to care for fruit trees in fall and winter is very important for the longevity of your orchard and harvests. Fall and winter care of fruit trees look different but each season is important. Today we're talking with an expert, Joe from Raintree Nursery.
Raintree Nursery was started in 1972 by Sam Benowitz with the mission of bringing the best edible plants from around the world to the Pacific Northwest. Sam dreamed of creating a place where American gardeners could access these plants and also become educated on how to grow their own food. Joe, one of Raintree's expert's and horticulturists, shares his knowledge today on fruit tree care.
Also, Raintree Nursery's ship all over the United States and are offering readers/listeners a 10% off coupon, use coupon code: modernhomestead at checkout!
Listen in below to the full podcast, Episode #242 Fruit Tree and Bushes Fall and Winter Care of the Pioneering Today Podcast, where we don’t just inspire you, but give you the clear steps to create the homegrown garden, pantry, kitchen, and life you want for your family and homestead.
How to Care for Fruit Trees In Fall & Winter
Melissa: I usually begin pruning my fruit trees between February and March here in the Pacific Northwest. As I'm out there, I'm definitely looking at my trees and orchard. For the fall and winter months, what are some important things that we should be aware of?
Joe: I'm going to speak mostly about the Pacific Northwest here, but fall and winter are totally different in your fruit tree care. The trees are in a completely different part of its seasonal cycle in the fall as opposed to winter. In fall your trees begin to close up shop, so to speak, for the winter months. They want to shut down a lot of their metabolic processes so they can save their energy, which is finite. Trees do have a finite amount of energy every year. They can't go out and get a second job, run a night shift, or pull overtime. Their energy income is fixed by the root system, but the amount of sunlight they get. So they have to save energy for growing during the very best period.
In the fall the trees pull their energy back into the roots. The sap comes out of the branches. The leaves come off. Any fruit that for whatever reason hasn't fallen let's go. The trees will bring all that energy down to the root system as opposed to the wintertime.
During the wintertime, the trees go into dormancy. Dormancy is like going to sleep like you and I have to go to sleep. If you don't get sleep, you feel terrible and eventually, your body stops working, right? That's the way it is for trees.
Dormancy is an absolutely critical process of caring for fruit trees and when they miss it, things get weird. Dormancy allows the tree to manage its sugars and its hormonal systems. The most common thing that will happen if a tree doesn't get enough dormancy is it won't flower. Therefore it won't make any fruit.
Melissa: Assuming for a tree to go into dormancy, temperature and daylight hours are a factor, which we don't have much control over. Is there anything we can do to help the tree go into dormancy? Or is it really weather dependent?
Joe: It's less light and more weather dependent. One thing you can do, if you have a tree that's potted as an example, is do not leave it in a warm place all the time. That happens to people; people have plants that they keep inside most of the time. They forget to put them out and let them go dormant.
Potted citrus is a common example of that or a tree that you might grow in a greenhouse. You have to manage that. You have to get the tree to a point where it's dormant but not expose it to temperatures so low that it's going to kill it outright.
Chill Hours for Fruit Trees
The other thing we can do is make sure that we are really diligent about is making good selections. Chill hours are hours below 45 degrees on average in a region. Select fruit trees that are within the chill hour range for your area.
There are trees that have chill hours under a hundred and those work really well. For example, the Dorset Golden Apple, you can grow in the Bahamas or warm climates. There are other plants, especially cherries and fruit trees, that have 8000 to a 1000 chill hours requirement. So if you're in Georgia, you're not going to be able to grow that.
Melissa: Chill hours is such an important thing with fruit trees and berry bushes as well, especially blueberries. A lot of people don't know that when they're picking out. They're just not doing their research and then struggle to get their plant to do anything. But definitely fruit production is pretty much zero.
When to Transplant Trees
Speaking of dormancy, when is the best time to transplant or move a fruit tree? I have always done it when the tree is in dormancy. I'm expecting you'll say the same, but do you have any advice on the best time to move a tree? Best tips on when to do it and how to do it so that you don't kill the tree?
Joe: Your instincts are absolutely right. When transplanting a tree, dormancy is the very best option.
Don't transplant fruit trees when the soil is saturated.
Soil saturation is defined by if you grabbed some soil and you squeeze it and make a ball out of it when you open your hand and you still have a ball, the soil is too wet. So even if the tree is dormant, that would not be a good time to transplant that tree. You need to make sure that the soil isn't going to literally suffocate the tree after transplanting. The roots must be able to exchange oxygen.
Otherwise, you can actually move a tree while it's growing, but there are consequences. Sometimes those consequences can be mediated and sometimes not. If you have to move a tree while it's not dormant, then you really should do kind of a cost-benefit analysis. There's no guarantee it's going to survives if you pull it out of the ground while it's still trying to grow.
Melissa: So your best bet for it to live and for you to do it successfully is to do it while it's in dormancy. I love that tip on the soil. I feel like my soil is very saturated most of the year.
Care of Fruit Trees in Fall
Melissa: What should you be doing in the fall versus in the winter months as your caring for your trees?
Joe: Again, fall and winter are completely different animals. Care of fruit trees in the fall is mainly leaving the tree alone. Fruit trees are super engaged in a bunch of processes that it's really important not to disturb them, especially if you want to have flowers the following spring.
Fruit trees benefit from a general late fall cleanup of your orchard, however. Any remaining fruit that is still on the tree, you should knock off. Rake up anything on the ground.
Fruit tree disease prevention
A lot of fruit tree diseases and a fair number of pests harbor in the fruit and even sometimes in the leaf debris over winter. Cleaning that out can make your orchard a lot easier to manage and care for your fruit trees in the coming months. It helps the tree not have to deal with disease factors, especially fungus.
When the leaves decompose it gets back in the root system and cycles through the tree year after year after year. That's one of the things we really don't want to happen. That's why you do that good cleanup in the fall.
When to Prune Fruit Trees
Joe: Well, you're not going to like the answer, but in winter, while the trees are dormant, there's plenty you can do on the east coast. They do a lot of pruning of deadwood, diseased wood, and sucker growth.
However, here in the Pacific Northwest, we need to be careful that you do not prune while it is actively wet because moisture allows bacteria and fungus to get into those brand new openings in the cambium layer that you've created with pruning.
Melissa: Okay, so I need to wait for a good dry spell. Normally I'm a fair-weather pruner so I don't go out and prune in the rain. After pruning how long should I be looking at the weather and hoping the weatherman is right? How long of a dry spell after I making my pruning cuts should I be looking for?
Joe: As much as possible really; two, three weeks. The tree needs time to compartmentalize that wound. Then it can ward off any disease or fungal growth, or even insects. We don't deal with insects too much here in the Pacific Northwest. There's not going to be a whole lot of pests that get into your pruning cuts. You can take off 100% of the deadwood though. If there's deadwood in the tree, it's obviously dead; there's going to be no danger of infecting the tree when you remove that.
In the winter you're free to do as much dead wooding as you want. But sucker growth and especially heading cuts you want to avoid.
Heading cuts are when you take the tip of the tree branch off. I personally avoid heading cuts no matter what, unless absolutely necessary because it affects the hormones of the tree. It causes excessive flowering and sucker growth because the growth hormones in the tips of the branches are removed. There's a growth hormone inhibitor that prevents excessive flowering and spur sucker growth in the tree. If you cut that all back, there's no control anymore and the tree will just grow as hard as it can.
Some apple growers do that on purpose. They want to tip back to make more flowers happen but the root system, again, has a finite amount of energy. So the more you asked that tree to do, eventually, you're going to get ahead of how much energy you can produce and the tree will go into decline.
Melissa: Here in the Pacific Northwest, I don't know that in the springtime I ever have two to three weeks of total dry weather up here in the mountains. I realize just trying to pick it for when you have the largest amount of dry weather happening, however, then when you get into having that drier weather, for me, then I already have bud break starting to happen. Is it okay to prune if you already have bud break or is it more ideal to just try to go for as many dry days as possible, but do so before your buds start to break?
Joe: This is my favorite question about growing fruit in the Pacific Northwest because the answer is, you prune in the summertime.
Almost all of the rules of pruning and the rules of caring and growing fruit trees are based on a New England or California environment. 99% of the literature is focused on California growing or New England gardening.
Now, imagine an area where you get a lot of cold and that your winters are really cold. Well, the thing about really cold winters is that they're also dry. Snow is not wet, nor is ice, not for the purposes of bacteria and fungal growth. 100% you can prune during the winter and because their summers are wet it's not a good idea to prune in the summer.
Here in the Pacific Northwest, it's the other way around. We have very wet winters and we typically have very dry summers. The tree is actually dormant twice a year: in the summertime as well as in the winter.
If it gets hot enough that the tree is transpiring more water, pulling more water out of the ground than they can replace, it will start to go into a sort of pseudo dormancy. At this point, it's 100% okay to prune your fruit trees. It remains dry, you're not going to mess up the hormones at all. The trees not strictly in full dormancy, but it's in dormancy enough that you're not going to upset its hormones. Provided you don't go crazy and remove more than 30% of the tree mass, then you shouldn't incur any problems.
In fact, fruit growers associations in the Pacific Northwest, a lot of the old guys, old codgers, are absolutely convinced that summer pruning is 100% superior. They believe it reduces suckering and reduced disease in ways that winter pruning simply can't. There's a lot to be said for summer pruning. I personally practice summer pruning myself and for anybody who lives here in Western Washington, I think it's the way to go.
Melissa: I love hearing that it does help with sucker growth because I actually have more on my apple trees probably than my cherry and plum. So deadwood do in the wintertime but the other wait until summer when it's semi-dormant and do the pruning then.
Joe: Yes, the way the fruit growers have explained it to me is you imagine the tree has a hundred units of energy. That's just a number. During the winter, all the energy is in the roots, so you have 100 units of energy spread about a hundred units of tree volume. If it's winter and the energy is in the bottom of the tree and you take off 20% of that tree volume, that hundred units, it tries to enter any percent of the tree. Well, there's 20% of the energy that has nowhere to go and so you get suckers.
Now, say that tree has 100 units of energy, it's up in the tree during the summer. This is oversimplification seems to work best for people to understand. When you take off that 20% of the tree in the summer, you take off 20 units of that energy too. Then it goes back into the root system.
In the following spring, you have a good ratio, you have 8o units of energy, you have 80 units of tree, there's not as much back pressure so to speak. There's not as much reason to grow extra suckers because you don't have excess energy.
Melissa: I am so excited to try that this year. I love doing experiments anyways so I'm excited to be able to document the difference because right now I have a clear picture of all the sucker growth. Then I can document this each spring by doing the summer pruning and see the reduction, hopefully, in sucker growth. I'm excited because I haven't pruned any of my apple trees yet.
Joe: I just want to reiterate that this is a gross oversimplification of why summer pruning works differently, but it is the easiest way to visualize how it works differently.
Melissa: I feeling that if you can't oversimplify something then you probably don't understand it as deeply as you should so I appreciate the oversimplification.
How to Water Fruit Trees
We've covered this quite a bit in our conversation so far about caring for your fruit trees and how that varies depending upon where you live, but do you have anything else you want to touch on when caring for trees, depending on where you live?
Joe: We've talked about seasonal pruning based on where you are, but there are also water needs. We need water in the summer and in the Pacific Northwest we don't have it. You're going to have to water your trees in the summertime until they're three years old. However, like the Midwest, Oklahoma, for instance, is an example of a place that you never need to water in the summer ever, but you may need supplemental water during other parts of the year.
Soil conditions are another thing that varies wildly from area to area. Even within your state, Eastern Washington, Western Washington, are incredibly different climates. Oregon and Washington, even different parts of Washington have very different soils so the kind of plants that you select and the kind of challenges you're going to deal with based on those sols are going to vary from place to place.
Micro-climates are a real thing that you can't get from a weather map when you can have up to eight degrees difference between one micro-climate and another. Somebody can grow fig trees just find or the person may struggle and they can be in the same city, it just depends on the little spot of land that you're working on.
Melissa: Absolutely. I talk about micro-climates and micro-zones a ton because I definitely experience them in my area.
Joe: The kind of pests and diseases that you deal with depending on where you are in the country are also hugely different. We grow chestnuts here in my area of Washington and do it pretty easily because the Chestnut Blight doesn't exist here. If you take the Chestnut trees, say to New York, they will die because they are not immune to blight. Conversely, the filbert blights are different on the East coast as they are on the West coast.
Again selection is important when you're dealing with this stuff. You can't just go to Home Depot or Lowe's and grab some trees and throw them in the ground and expect them to work. Trees are not car parts.
That's what your extension services are for, that's what your horticulturalists are for, that's what the experts at the nurseries are for… to consult with so that you can make sure you get plants that are going to work for you. Otherwise, all your going to do is waste your time and money and you'll harvest frustration instead of delicious fruit.
Care for Young Trees
Melissa: Hopefully this will help my readers and listeners to learn a lot faster and avoid some of these pitfalls that I myself have fallen into. Besides making sure to water that first year from when you plant as opposed to an established, more mature tree, what are some other things we need to know about for caring for younger trees?
Joe: Water is pretty much the game with younger fruit trees. Deep watering, in particular, is really crucial.
You're looking to dump 10 to 20 gallons at a time, not over the course of a week, but once per week on those root zones. That's going to drive that water deep in the ground and it's going to encourage the roots to go after it.
If you do that for three years roughly, and everything has gone well, of course, there's no guarantee, that tree should have deep enough, large enough root system that it's able to access underground water resources beneath the top six inches of soil. Your needs for supplemental water are going to significantly reduce at that point. If you do that labor for the first three years, it will save you so much trouble later on.
Caring for Mature Trees
For Mature Trees, water isn't a problem for them because if everything's gone well they have plenty of water resources. But you're mulching, managing the soil, inspecting the trees…you want to make sure that bark is in good shape.
Check for insects to make sure you don't have any. You want to make sure your diseases are in check. Make sure there's a lot of organic matter for those trees because they eventually run out of food. The way nature designed it, is that the leaves fall and decompose, animals come in, fruit falls, animals poop, the fruit decomposes. There's a lot of organic matter going on.
You have to mulch the trees. Mulching prevents grass from competing with your tree roots. Grass is super competitive plant in your orchard. People don't really realize how incredibly aggressive grass is, how tight it's root mats are, how much of the nutrients in the soil that it pulls. Keeping grass out of the drip line of your tree is a big deal.
Melissa: Since I'm removing the leaf matter to try to keep disease and pest down naturally, what are things that can be done to fertilize instead? When is the optimal time to be adding things like compost or chicken manure? Is it in the fall or spring? Or both? What's your preferred mulch materials?
Joe: Manure, of course, is great, unless it's chicken manure. You'll want to compost that for a period of time so that the pH and nitrogen aren't too harsh on the tree roots.
You want to apply it late winter, early spring. You don't have to dig it in, you just throw it on and the rain takes care of the rest. Straw, manure, even wood chips, especially those that have had three or four years of decomposition already are excellent amendments for your trees.
If possible you want to get a four-inch layer going because it'll keep that grass out. You can also use cardboard, which is kind of a cheat but it's really neat because it gives the mycelial fungus, which is really beneficial for the tree, a place to grow and establish if it's not already in the soil. Cardboard is also hard for grass to grow through.
If you don't have someone that's going to slip and fall on that cardboard, it can be really great, especially if you set it up in the fall so that it has all winter to decompose. That way you don't have a slipping hazard come the springtime when you're starting to poke at your trees a little bit.
Rabbit manure is widely considered the most valuable manure for plant growth, especially grapes. Rabbit manure is like primo numero uno for grapevines. But I found that it is pretty much for everything else as well. Just go ahead and throw it on. I've even planted into it directly with no soil and it's the biggest cabbages I've ever seen.
Chicken and cow manure have to be composted. Pig manure is basically unusable no matter what so you don't want that.
Fruit Tree Disease Warning Signs
Melissa: Earlier we touched on keeping an eye out for disease, but for someone who's brand new to this, what are you typically looking for? What are the warning signs of disease? I know there's a multitude so we can't pinpoint every single one, but what are some things that are definitely big warning signs that there's a problem?
- Your fruit quality is poor. That's the one most people notice first. Brown rot on plums is an obvious example for Asian plums in particular. They get wet in the spring, the blossoms start to get a little bit of brown rot and the rot transfers to the fruit.
- Tip dieback
- Splitting canker. An oozing mass that's on the tree. It's very common on cherries.
- Fruit splitting
- Wound in the tree that is oozing
The list is really, really long. Mostly you want to look at the tree and ask yourself if it looks right.
If it doesn't, take a picture and give someone a call or visit your local extension office. They're the experts where you live. They spend all their time looking at people's pictures or inspecting cuttings that have been brought in, diagnosing disease and giving advice. It's what they do and you should take advantage of that as much as possible. A diagnosis over the phone or out of a book can be very difficult.
A lot of times it's good to get a picture or even take a cutting, if it's something that's all over your tree and you can take a clipping. That's the fastest way to do it. The faster you get your disease diagnosed, the easier it is to treat.
Melissa: I noticed on one of my fruit trees, there's damage on a branch like it has a wound all the way to the heart of the branch. Should I remove that branch or keep an eye on it?
Joe: That's a canker, which is a dead section of bark on a branch. There's a lot of reasons it can happen. There's abiotic damage which is a mechanical injury where it actually got bit by an animal, knocked or cut, a car drove into it. There are all sorts of things that happen to trees, but it may also be a pathogen, especially a fungus or bacteria. Without knowing you typically cut those off. What color is the wound in the the wood, underneath it?
Melissa: The heartwood is white, but the actual wound is dark.
Joe: That is reactive tissue. It's very much like scar tissue. Cut that off and then make sure that the heartwood is not black. If there are black spots or blackness to the heartwood you have to keep cutting because what you have is anthracnose and that will eventually work its way into the trunk of the tree and kill it.
Melissa: So I will remove that but I don't know when I have dry weather. So better to remove it now or wait until I have dry weather and then remove it?
Joe: Well, for your specific situation, remove the diseased part. Then, during a dry period, take the rest of that branch off; you're going to remove it at the branch collar.
Melissa: So don't do it like my final cut at the collar, just do it right where that is and then to the correct final cut later when we're dry.
Joe: Right, that way if some disease gets into that cut, you're going to remove it the rest of it anyway and the tree will be able to heal naturally during the dry conditions.
When to Treat Fruit Trees
Melissa: What diseases and infections need to be treated in the dormancy phase versus active?
Joe: Typically there's not a lot of diseases, aside from cutting off diseased wood – what we call cultural control. Most spraying is reserved for the end of winter, or during a specific life cycle of a pest.
The dead of winter is not really what's best for tree spraying. The spray washes off, it doesn't stay on there forever. Peach leaf curl is an example. Peaches grow, you wait a couple of weeks before those leaves come out, and then you spray the tree with copper sulfate fungicide. It's on there long enough to prevent the peach leaf curl and then washes off, which is great because you don't really want that on your peaches.
Every disease is going to be different and has different treatment requirements and different treatment tools. Again, you need to diagnose and get the right information so you can do the right thing.
Melissa: What would you suggest for a novice who's just learning to care for their own orchard?
Joe: Watering is the biggest hurdle everybody has. Set up a good watering practice. Plant your orchard 500 hundred feet or closer from your water sources. Nobody wants to haul water 500 hundred feet to be able to water their trees. That's one of those things that you need to think about in your planning stage.
Proper pruning is another big one. Pruning tree badly is worse than not pruning a tree at all. You'll cause more problems, more disease, more malformation. Everybody needs to learn to prune. Pruning is learned best through actually getting out there and pruning your trees. You can read and take classes but getting out there so you can see why things are the way they are and develop those skills; develop the eye for it.
Those are the two most important things.
Where to find Raintree Nursery:
More Resources for Growing Fruit:
- How to Prune a Blueberry Bush for a Larger Harvest
- How to Plant Raspberries – Soil Prep, Growing & Caring for your Raspberry Plants
- How to Prune Raspberries
- How to Prune Apple Trees
- How to Grow Elderberries
- 5 Tips to Starting an Orchard & Growing Fruit
- Planting Berry Bushes & Fruit Trees (How Many to Plant Per Person)
- When & How to Plant Fruit Trees
- Planting a Fruit Tree Guild