I planted this pluot tree for my grandma a few weeks ago and made sure to paint its trunk to protect it from the sun; I hadn’t so protected a pluot tree that I planted for my mom eight years ago and look what happened.
I’ve seen a lot of trees in other yards and school gardens lately with this problem. Check your fruit trees; I hope you don’t find it, but check.
Effects of sun damage
The good news is that this damage from sunburn on the trunk does not usually kill the tree, at least not immediately nor if you can protect the trunk from further damage. My mom’s pluot tree in particular still grows and bears fruit although it doesn’t perform as well as the trees without damage that grow next to it.
My theoretical explanation for this is that the trunk now has less capacity for sap flow — for water and nutrients to flow up from the roots to the leaves, and for the energy that the leaves create to flow down to the roots. It is roughly analogous to pinching off some of the blood vessels in your legs; they’re still going to work but not as well.
Another effect of sunburn on a trunk is that it is attractive to certain pests. Borer insects sometimes show up to exploit the easy entry point into the tree. (Read more about tree borers on the University of California IPM website here.)
Which trees to paint
So I paint the trunks of almost all fruit trees that I plant nowadays. There is no downside to painting trunks, save the minimal money and effort it takes to do the painting.
Last winter, I planted this apple and painted its trunk:
Two winters ago, I planted this pear and painted its trunk:
Also two winters past, I planted this cherry and painted its trunk:
These are the types of trees that especially need their trunks painted: pluots, apples, pears, cherries, and plums too. What do they have in common? They are inclined to grow their branches upright, especially in their early years when they’re not bearing much fruit. These vertical branches provide little shade for the young trunk whose bark is thin and susceptible to the sun.
Another type of tree that is extremely sensitive to the sun in general and therefore often needs its trunk painted is avocados. I planted this avocado the other day and will be sure to paint its trunk as soon as this week’s rains pause:
On the other hand, I planted these avocados and found it unnecessary to paint their trunks because their lower limbs are shading their trunks well:
How to paint
There are a few expensive products that you can buy to paint trees, but I just use cheap white latex paint (interior or exterior, it doesn’t matter) and I dilute the paint about 50 percent with water. Many other people have done this for many years in many locations. It works.
Paint all the way down to the soil and all the way up to the lowest limbs on the south side of the trunk. It is the south-facing side of the trunk that usually gets sunburned although it can also happen to the east and west sides, depending on what is around the tree. So I always paint all sides except the north just to be safe. The sun never shines strongly from the north here in the Northern Hemisphere.
After initially painting a tree’s trunk, usually, the tree grows and bears fruit and its branches become more horizontal under the weight of the fruit. These branches then shade its trunk such that no later paintings are required. Here is a five-year-old pluot tree in my yard whose trunk I painted at planting, and which now has weeping lower limbs that shade its trunk:
If, however, a fruit tree doesn’t begin to protect its trunk from the sun like this, then that remains our responsibility. Grab the paint can, and get it done well before summer.
A list of all my Yard Posts is here.
Another great article, Greg! I just painted with a gallon pump sprayer -mixed half water and half paint – about 25 fruit/fig/citrus/avocado trees on our high density farm. Thank you for the good read. I hope all is going well!!
Thanks, Aiden. Same to you way over in Texas!
I’ve been thinking of doing this but wonder if wrapping the branches and trunk with rolls of lightweight gauze bandages or other lightweight cloth would work as well? Kinda like a M.A.S.H. unit during the hottest parts of summer. 🙂 We have one Haas and one fuyu persimmon and are in coastal OC, so we don’t need year-round sun protection.
Hi Barb,
I often wrap the trunks of young trees loosely with shade cloth, and that works fine.
how long should i wait after cutting my avo tree after cutting down to the trunk
Aiden, glad to see you using a pump sprayer. I always paint my trunks every year. And just knowing that you are having success with this equipment, I’m going to try this too! Thanks for the info.
Just be sure you don’t have anything nearby that you don’t want painted. I tried this last year and got it all over some rocks I used to make rings around my tree. With white paint spatters everywhere under the trees, it looked looked like I had quite the bird habitat. This year, I’m going to lay down a couple drop cloths. I wish I remember to do this before mulching but I can always add more much.
Any fruit from that cherry tree yet?
Hi Ben,
It’s only flowering for the first time right now. Maybe we’ll get our first few this year. I sure hope so.
Hi Greg, I’ve always wanted to plant a cherry tree or 2. Nothing large, maybe a dwarf? But I was wondering what type of cherry would you recommend? I love Bing cherries the best. I live just outside of Sacramento, but in Sac county, just so you have some idea of the weather up this way. I also wanted to add that our avocado tree just thrilled us this year. It was our first bumper crop in the 7 years we’ve had it. We got almost 75 avocados on it. Wow. I’ve been adding them to our fruit/veggie smoothies, they are so delicious. A neighbor told me she freezes her avocados when they get too ripe. So I did that too to see what would happen. When I took it out to thaw, the skin got a bit wrinkly but the fruit itself was still delicious and green. So now I know I won’t have to give them all away so they’re not wasted. LOL I can freeze them! Thanks as always. Love your articles!
Hi Debbie,
I’m not sure about cherries up your way because I’ve been told that the Spotted Wing Drosophila pest is overwhelming. Have a look at this article by Don Shor of Redwood Barn Nursery in Davis: http://redwoodbarn.com/DE_Drosophila.html
Great to hear that you’re getting good avocados from your tree up there! Do you know which variety you have?
I’ve frozen the avocado flesh before but never tried freezing a whole fruit. I’m going to have to give that a try. Thanks for the tip
What variety of avo did you plant? How many avo trees and varieties do you have now? As mentioned I just planted a Reed and whitewashed its trunk.
Hi Frank,
That one is a type of Hass. Since Hass has been around for almost a century and it’s been grown in great numbers all over the world, strains and sports have been noticed and I like trying them out when I can.
I don’t have very many avocado trees that look like trees since I only moved to this property and started planting in 2013, but at the moment it’s technically somewhere around 30 trees and 35 varieties if you count newly planted trees and varieties that are only single grafted branches.
I’ve never painted my stone fruits and haven’t had problems, but citrus and avocado are another story altogether. I’ve had massive sunburn on my spindly avocados but they still live just enough to taunt me. I top worked a citrus to perform my own grafts (which failed) and ended up with massive sunburn on the trunks that were no longer protected from the sun. 5050 water with white latex is what I use now as needed.
As for the citrus, I found a guy who did some successful grafts and he showed me the painting trick. And as for the stone fruit I’ve never painted, I think my location near SDSU helps; we just don’t get that hot and sunny early in the season so the leaves come in before it’s time to do damage. I imagine that the further east you are the more this would be needed.
Hi Bob,
I think you’re definitely right about location being important.
It so happens that I planted seven trees in my mom’s backyard on that day eight years ago, and I did paint the ones that I headed (in order to induce low branching). Out of the ones that I didn’t paint, two now have sunburned trunks (that pluot and a plum) but the others are fine because they grew spreading branches that shaded their trunks. I thought I would be able to predict which trees I needed to paint, but I was a bad forecaster.
Thanks for all your posts Greg! I’ve found them extremely useful, even here in South Texas.
I am a very ecologically-minded person and applying plain white latex paint on my fruit trees makes me uncomfortable, especially since it will leach into the soil… I suspect that standard latex paint contains some toxic stuff in it. I’ll look for alternatives, but I’d like to know what your thoughts are about this, since you also seem to be very eco-minded.
Hi Jorge,
Thank you. This is actually something that I’ve never considered, I guess because the amount used is so small and it goes on the bark of branches only — nowhere near anything I eat. But that’s not the only thing to consider, and I’m glad you brought it up to make me think about it more.
My paint can doesn’t show its ingredients and I can’t seem to find them elsewhere.
I know of a couple alternatives. One is a product that is based on kaolin clay, called Surround WP. I’ve never used it myself, but I know people who have and who say it is effective. Unlike latex paint, Surround must be reapplied occasionally.
There is also a product made by IV Organic. I’ve never used this either, and I can’t find its whole list of ingredients.
For whatever it’s worth (not much, in my opinion), both of these products are OMRI listed so they can be used in certified organic operations.
Thanks for adding this info. I’ve seen that elephants use clay as sunscreen! I assume they need to protect their skin from the sun since their fur isn’t very hairy, just like humans. I can now relate this to trees as well! Cheers
I like that! I forgot to mention that if you’re just protecting the trunk, you can use a wrap of durable paper or plastic that can be removed once the tree grows enough to shade itself.
Again great ideas Greg. When I haven’t had the time to reapply paint I’ve painted the inner cardboard roll from a paper towel cut it down one side and wrapped that loosely around the trunk and secured it with twine.
There’s one great product here which is kaolin clay and seaweed based as a protection against gall wasp and weather extremes. https://vasilisgarden.com/index.php?route=product/product&product_id=284
Also check out a link I left after Greg’s response about IV organics. Organic gardener’s has a lime based ‘white wash’ paint which you may prefer. It’s cheap and very easy to make.
Spot on Greg! I’m an organic gardener and I use these ingredients https://www.organicgardener.com.au/articles/lime-based-whitewash
Super cheap and needs yearly application but worth.
I’ve also used the IV organics product and it’s great but much more expensive.
There’s a YTer who’s growing in full sun in Phoenix, AZ, area who uses this 3-in-one organic product to protect from sun and borers. I haven’t tried it, but from what I’ve seen of their place on Edge of Nowhere Farm I trust their experience: https://ivorganics.com/product/3-in-1-plant-guard/
Do I have to paint my avocado tree on tropical climate, like my country Indonesia. I’ve planted Hass and Shepard avocado amongst local Indonesian origin avocados. Many people said that Hass and Shepard won’t bear fruit in tropical country, but I want to try.
Hi Toton,
I would think that avocado branches and trunks could get sunburned where you are just the same as they do here.
It’s true that avocado varieties perform differently in different climates, but I’d be surprised if Hass and Shepard don’t bear any fruit at all for you. What I’ve been told is that Hass fruit are small when grown in lowland tropical conditions (if you’re at a higher elevation, then that might make a big difference). I’m glad you’re giving them a try though because that’s the only way to find out for sure.
Thanks for your explanation. BTW, I subscribed your youtube channel. So, I’m always waiting for your new videos.
Thanks. I only wish I had more time to make more videos. Sorry I don’t make them often.
Hi Greg! I’m a bit late to this thread. I have 6 beautiful young citrus trees south facing here in Scottsdale, AZ. I just got tree trunk paint from Arizona’s Best and am planning on painting the trunks this upcoming Saturday night. We have reached our temps of 101 (heat just getting started here)
Is painting them now too late?
Everything I see online shows people painting them in spring, NOT in hot months.
Thank you 🙂
Hi Darius,
Painting as soon as possible is the right time. Most people paint in spring only because they want to be ahead of the game, and occasionally spring heat waves are fierce. Hope your new trees have a great first summer!
What kind paint are you recommended? Organic not organic, external or regular house paint?
Hi Michael,
As I mentioned in the post, I usually use white latex paint, external or internal doesn’t seem to matter. This has been used by farmers for many years.
In my reply to Jorge’s comment above, I also mention the clay product called Surround WP. It is certified organic. I have used it lately. It works too, although it’s not quite as long lasting as the white latex paint.
My nursery go to guy here in Gulf Shores, AL suggests a zinc powder mixed with water to a slurry consistey and painted on. I have orange, lemon, and Satsuma trees. Going to try this..just bought the house and was not sure how to take care of them..lived in vthe mountains of Colorado last 20 years.
I purchased a Santa rosa plum last fall and bought paint at a local nursery.I was busy with fall gardening chores and instead of doing research on painting fruit trees I just followed instructions on the can.Needless to say, I painted the entire tree, all 5 feet of it including several branches. Now that I took the time to do research I realize I was supposed to only paint the trunk. Will my tree survive. Or die? Last summer we had a full week of 118 degree weather.
I had a beautiful Tangelo That gave us fruit enough for the whole neighborhood plus family, had it professionly trimmed and cut all the lower and some canopy, WELL it killed my tree, now we have a tree coming out of where the Tangelo was and it looks very healthy and is 6ft tall, could this be a sucker???
Greg,
I have several mature El Mirador Fuertes at my dad’s house in Pasadena that I’m trying bringing back to lo life after years of neglect. I’m making some good progress! However, I’ve noticed large portions of bark have begun to detach from the limbs. Sometimes whole pieces 1 to 2 feet in length. This leaves large areas of the cambium totally exposed to the sun, which then begins to dry and harden. Might you know what could be causing this and how to prevent future detachment of bark? The trees are approximately 110 years old and anywhere from 15-30 feet tall.
Keep up the great work and thank you for all the knowledge!
Hi Peter,
Without seeing the trees, I can say that this is what happens to sunburned bark. It ultimately sheds. Fuerte is especially prone since it has so many horizontal branches.
Protecting that part of the tree with white paint or something similar is key for the short term, and for the long term you’d want foliage to grow above it to protect it from the sun. The good news is that limbs can still live well with the bark gone on one half (in other words, one side of the limb is dead).
That makes sense. The limbs were exposed to the sun for many years when the foliage wasn’t pronounced. The good news is soil aeration, watering, and a heavy layer of mulch and the tress are doing well, though I still find shedding bark on the ground every once in a while. Thank you for the great info and inspiration!
Hello Greg. Some years ago I painted my fruit tree trunks with an oil mixture. Supposedly keeping the overwintering critters from crawling up and into the tree. Did i february. It worked amazingly well! However I am unable to remember or find the recipe. I had canola oil wanting to be rid of so used it…….but with what? Painted trunks with old pantbrushes. Are you able to help me? Sure hope so. Thank you
I’ve noticed that if I don’t paint avocado branches exposed to sun, they form their own bark. That must take energy from the tree. So I paint them with 50/50 latex white paint. It’s fun, like putting sun screen on a beautiful woman.