The damage you see in the above photo is called Vertcillium Wilt. Verticillium wilt attacks all kinds of plants, usually with devastating results. I’ve had it attack at least three if not four of my pretty mature Japanese maples.
Verticillium Wilt is a soil borne, fungal type of disease that affects the plants ability to move water to certain parts of a plant, causing that section of the plant to fail, the die. There is no chemical control, prevention or cure. It’s just something that happens, but . . . but . . . but . . . it is not the end of your tree!
I’ve had this happen to at least four Lace leaf weeping Japanese maples in my landscape and it’s happened over a period of time. I’ve read all kinds of explanations of what exactly is going on in the soil to cause this, but quite honestly, in all four cases my soil conditions were different, never soggy, just different soils. Didn’t matter, it still occurred.
You can take my opinion for what it’s worth and my only qualifications to offer such an opinion is to say that I’ve not studied a great deal about plants but I’ve spent the better part of my life, starting at the age of sixteen, I’m 63 today, crawling around in the dirt, working with plants on a daily basis. You can not stare at that much dirt and that many plants and learn valuable things through shear observation. Often times, those observations are more accurate that what you find written in text books.
My opinion about Verticillium Wilt on Japanese maples?
There is nothing you can do to prevent it and there really is no cure for it except to prune it out of your plant.
There are certain ground rules for planting and caring for Japanese maples and I’ll cover those here. If you follow these recommendations I think you can be assured that you have done everything you can to give your Japanese maples a good home. But Verticillium Wilt can still occur and it is certainly going to be heart breaking, but in most cases the trees can and will recover nicely.
Things to know about planting Japanese maples.
- Japanese maples are an under-story tree and when young they really don’t care for or often don’t do well in full sun. Part shade, part sun is where they are the happiest. Too much shade and they will turn green and lose their beautiful colors.
- Japanese maples hate wet feet! Do not plant them in a wet area, or an area where a downspout drains. They love soil that is mostly dry, just moist enough to give them the moisture they need. Never soggy, simply cool and moist to the touch.
- Like all plants, Japanese maples will fail quickly if you plant them too deep. It will kill them! Whether your tree is balled in burlap or in a container there is a root crown right at the soil level. When planted that root crown should actually be about 1.5 inches above grade if not higher. Then mound the soil up and over the root ball.
- Mulch the tree with about 2″ of bark mulch too keep the soil around the roots cool and moist.
- Do not pile mulch up around the stem of the tree. It will rot the bark and kill the tree.
- Stake the tree for at least a year so the roots can get established without the wind rocking the tree back and forth constantly.
- If planting your tree in clay soil it’s best to plant it even a little higher than described here and back fill around the root ball with the clay that you removed from the hole.
- After reading #7 you now know that I am bona fide crazy and full of you know what. What kind of advice is that?!!! It’s good advice, that’s what it is! If you dig a hole bigger than the root ball in clay soil, then back fill around that root ball with some kind of loose, porous material all you are doing is allowing excessive water to enter your planting hole with no way for that water to escape. It’s like filling the bathtub with water and submerging your plant in that water.
- Here’s a little known fact that most people don’t understand. Plants, just like people, will drown when submerged in water for an extended period of time. The roots of a plant need to breath. The roots have to be able to transfer oxygen from the air, through the soil, to the roots. If they can’t because the roots are surrounded by standing water that plant is going to die.
- Fertilizer is worse than heroin or fentanyl! The plants in your landscape do not need fertilizer. I never fertilize the plants in my landscape at home, or in the landscape plantings around my nursery. They just don’t need it and too much can and will kill them. Especially Japanese maples! They don’t even know what to do with fertilizer!
- Don’t believe me? Look here! Those plants have never been fertilized!
- Water your Japanese maple as needed. When first planted it will need some water two or three times a week. Not a million gallons of water! Stick your finger in the soil. If it’s dry, water. If it’s cool and moist or soggy don’t water. If you get into a hot and dry situation water your Japanese maple and other plants in your landscape thoroughly about every 9 days.
Back to Verticillium Wilt on Japanese maples!
If your Japanese maple suddenly has a large branch, or a pretty big section of the tree that appears to suddenly just up and die. More than likely it’s Verticillium Wilt. It usually starts with some discolored leaves, then the leaves turn brown and crispy and often will not drop from the tree right away. They just curl up and turn brown and crispy and often stay on the branch. Once your tree gets to this point it’s probably too late to save that particular section of the tree or that branch. Before you remove any branches do a scratch test to make sure that they are dead.
This is how you test to see if a plant, or a branch on a plant has died. Just scratch the bark of your plants with your finger nail. If the tissue below the bark is green and firm your plants are fine. If the tissue is brown and mushy that part of the plant is dead. Once that tissue below the bark becomes brown and mushy there is no saving that part of your plant.
As I mentioned earlier in this article, I’ve experienced Verticillium Wilt on several of the Japanese maples in my landscape and in each case I was able to prune away the dead part of the plant and eventually have the trees make a really nice recovery. After pruning you are obviously left with a big gaping hole in your plant, but you’d be surprised at how fast it will completely fill in. I’m not talking days, weeks or months. It is going to take at least two or three years to fill in nicely. But it’s always worth the wait to save a beautiful Japanese maple.
Japanese maples have really hard wood so you will need really sharp shears of maybe even a pruning saw to remove the dead branches.
Sterilize your tools as you prune!
Before you start pruning clean up the blades of your pruning tools with alcohol wipes or something else suitable. Then clean the blades after each cut.
Do I do that? No. I’m a maniac! I’ve never done that. But I recommend that you do as I say, not as I do. I take chances.
Questions, comments or mean things to say? Post them below and I will respond.
When to prune Japanese Maple
Easter,
Anytime it needs it, summer, winter, doesn’t matter.
my acer palmatum is about 20 years old it is now showing something it has never shown before around the old blossom the leaves are withering all this happen on the lower and older growth what could this be please
Rodney,
Honestly, I don’t know.
I bet you read this word alot…HELP!!!!!! I planted a Bloodgood Japanese Maple in 2015 (I’m in mid-Michigan). I’m guessing that it’s, I don’t know, 12 feet now. It got full and heavy in the middle, so after watching many videos on pruning and Bonsaid shaping, early last winter 2019, I hard pruned it because I wanted it to look more Bonsai shaped. This 2020 spring, one tiny short lower branch put out leaves but no where else. Did I kill it or is it in shock and will start producing next year? I cut about 1/4 of it out 3 years ago where it died and it filled in beautifully in 2018.. Now the hard prune. It doesn’t look like it will be leafing out this summer. Should I just wait and see what happens? I was told by the nursery in 2015 to plant it in full sun. It gets shade after 6 p.m. Your thoughts, Mr. Genius tree guy!! So glad I saw your site!
Barbara,
Heavy pruning should be done when the tree is dormant, if not it could seriously damage the tree. But you said you pruned in winter, that really shouldn’t set it back. I’d just wait it out and see what happens.
Thank you, MIke, for responding!!! You’re awesome! Since that one tiny branch leafed out, I think I’ll wait it out. It was dormant with most leaves already having fallen off so it must have been November-ish. Again, thanks!
I have a red dragon Japanese maple that was planted by my Gardner three years ago. Last year in spring I notice several bottom branches were dead and had no new growth. Those branches were trimmed off.
This year in noticed a larger area of lower branches not producing new growth and appear dead. Top branches are blooming. New growth.
Tree is in a sun shade area in front of the house. I’m afraid by this time next spring I’m going to loose these beautiful specimen.
Any suggestions.
Robert,
I don’t have any suggestions other than to prune out any dead branches. The tree in this post was severely damaged and all dead branches removed. It looks terrible. But this year it is leafing out nicely and I expect it to recover fully. This is how you test to see if a plant, or a branch on a plant has died. Just scratch the bark of your plants with your finger nail. If the tissue below the bark is green and firm your plants are fine. If the tissue is brown and mushy that part of the plant is dead.
We just planted two very young Crimson Queen Japanese Maples. We live in Alabama with that southern red clay. When planting, we mixed with planting soil and the red dirt that was dug up. That was a little over a week ago. They have since started showing signs of shock or dying, including branches that are completely dead. There is still some healthy parts of the tree and the leaves are still beautiful on the branches that are still holding on. What do you suggest for the dead branches without killing the rest of the tree? Is there any food we should add all v with watering to give it more life? Thanks in advance for your advice.
Janet,
It’s really rare for trees to fail that fast. They are either planted too deep, the hole is retaining too much water, or if a fertilizer was applied it could have seriously damaged the plants. For one, I’d raise them up so the root crown is at least 2″ above grade then mound soil over that. The soil you mixed in could make the situation worse because water is getting in too easily and not escaping.
Thank you Mike.
No saving it. Maples can outpace the disease, but it.is vascular and runs from the roots up. It’ll catch up when the tree slows down.
I’m not sure about that. I’ve had two very mature Japanese maples that were affected. I pruned out the dead branches and the trees thrived for years and are still doing well.
I have two Japanese Maple trees and one has the verticillium Wilt. The other one all the top part of the tree the leaves fall off and I thought it was dead. Then it started to grow branches with leaves from the trunk. I don’t know if I should cut Off all the top branches and let the bottom ones that are living grow bigger.
What would you recommend?
I live in the Chicago area, so there is nothing I can do now but spring will be here sometime.
Thanks for your help.
Monau
Mona,
I’d wait until the tree leaves out in the spring, then remove any branches that are completely dead. This is how you test to see if a plant, or a branch on a plant has died. Just scratch the bark of your plants with your finger nail. If the tissue below the bark is green and firm your plants are fine. If the tissue is brown and mushy that part of the plant is dead.
I love roses. I have about 25 or 30 bushes plus or minus. I collected a few in the last 40 years. I am 86
years old. 2019 was a bad year for me. I has 3 serious accidents at home including a broken neck. So
my roses is all I can do now for gardening. I am slowly healing. I wish I could afford your letter, I
barely get by on social security. Both my wife and I are disabled. She also is 86.
Arthur,
Wishing you the best! Take care and enjoy those roses.
Thank you for posting this! I have a dwarf Acer Palmatum Dissectum right near the waterfall of my little pond, and every once in awhile i see this happen, just to a branch, and by habit, i cut it out after checking to make sure its really dead. Didn’t know what caused it, but I think you did! Thanks for the great info. I watch ALL your videos. You are a great teacher! Thanks again!
Thank you Cathi, I appreciate that.
In the section “Things to know about Japanese Maples, section 1,” it states that “too much shade and they will turn green and lose their beautiful colors.” Shouldn’t that say “too much sun”?
Don,
No, that statement is correct. Japanese maples in the shade lose their color and turn green. That’s pretty much true for most plants with vivid color.
This is the best advice I have ever read. You explained planting in clay soil perfectly. Thank you for taking the time to help us see how to better prepare our plants for a a more comfortable and prolonged life.
You’re welcome Angela.
Hi Mike. What are the light green plants beneath the tree?
Belinda,
Those are hosta but unfortunately I don’t remember for sure what variety they are. Possibly Happy Days??? I just don’t remember. You’d think I’d be better about keeping track but they are probably patented and I had no intention of propagation them when I planted them.
Hi Mike,
Well I just purchased 400 red Japanese Maple seedlings. I’m very nervous Bc I don’t want to do something wrong and kill them when I get them. So the probably be shipped out to me in April since I live in Pennsylvania. My question is how deep do I plant them in my raised beds? Do I leave an inch of the plant in ground or not that much? Thanks for any help I appreciate it
Robin,
Two things.
1. Depending on where you got them, they might arrive all flushed out with new growth and it’s still too cold in your zone to put them outside. If they are dormant when you get them then that’s not an issue.
2. Just barely cover the root ball with soil but keep them watered since they are planted so shallow. But you don’t not want soil up on the stems.