Help with my red japanese maple (over fertilization)

[MindMint]

Hello everyone,

I recently started using a chemical fertilizer instead of a bio-fertilizier for my red japanese maple and might have used way too much fertilizer. The symptoms started appearing a week after fertilizing, whereby the edge of the leaves became step by step darker and turned brown. I got very scared and decided to repot the tree without touching the roots. I repotted the tree exactly a week ago but still do not see any improvement in the leaves that are still getting dark spots. I have no idea what to do anymore. I have attached some pictures of the roots and of the leaves. Does anyone have any idea, if the tree can recover?

Thank you very much

 

[just.wing.it]

Those roots don't look untouched to me....it looks bare-rooted.
In my experience, doing that will kill it....oce its leafed out.

I think I've fertilizer burned stuff before....I just flush the pot with water a few times and use less next time.

Good luck!


Welcome to the NutHouse

 

[MindMint]

I washed out the roots on purpose because I read that it might help in case of heavy over fertilization which i think is what I did. Do you think I damaged it even further by washing the roots? what do you mean why it will kill it once its leafed out?

 

[VAFisher]

Most trees dont like their roots messed with after they leaf out. Thats why people repot just as buds are swelling in late winter / early spring. This looks like a young tree so it might make it. Nothing to do now but wait and see.

 

[VAFisher]

That looks like sun or wind damage to me as opposed to fertilizer damage. Tender leaves can get easily damaged by wind in the spring.

 

[penumbra]

I got very scared and decided to repot the tree without touching the roots.

This isn't consistent with what you have actually done. You should have posted this question before you bare rooted the tree. I think this rough treatment is worse than the over fertilization if that is what you actually did. There shouldn't be any guesswork here. You know whether you over-fertilized it or not unless you ignored the directions on your fertilizer. You also did not mention the kind of fertilizer or why you think you overdid it. And you have not posted where you live so we have no idea what your climate is. It really does look more like environmental damage as has been suggested.
In a nutshell, you have not given us enough information to make an informed decision.
At this point, not knowing even what type of soil mix you have used, I can only say keep it in the shade and pray. I hope it lives but have my doubts.

 

[MindMint]

This isn't consistent with what you have actually done. You should have posted this question before you bare rooted the tree. I think this rough treatment is worse than the over fertilization if that is what you actually did. There shouldn't be any guesswork here. You know whether you over-fertilized it or not unless you ignored the directions on your fertilizer. You also did not mention the kind of fertilizer or why you think you overdid it. And you have not posted where you live so we have no idea what your climate is. It really does look more like environmental damage as has been suggested.
In a nutshell, you have not given us enough information to make an informed decision.
At this point, not knowing even what type of soil mix you have used, I can only say keep it in the shade and pray. I hope it lives but have my doubts.

I am pretty sure I over fertilized because I put way more than what was instructed given that I thought that the amounts are similar to the organic fertilizer I used before which wasn't the case. The chemical fertilizer is 6 4 6 NPK. I live in northern Germany in Hannover, which is a eastern continental climate. I would've also thought it was environmental damage had my podocarpus also not shown signs of darkening needles (I fertilized it at the same time but it didn't get hit as hard). The soil mix is a bonsai soil mix that I got from a local bonsai shop. The tree had already sustained environmental damage before and that looked a lot different, which is why I didn't think it might be environmental damage. I have kept the tree in a shaded spot that is protected from wind. So there's nothing I can do here anymore right?

 

[MindMint]

Oh and I don't think it's environmental damage because I also have 2 other maples that are doing super well. I did not feed those with the chemical fertilizer

 

[penumbra]

Sorry, I have nothing else but wait and see. Someone else may pipe in with an idea or two.

 

[MindMint]

Sorry, I have nothing else but wait and see. Someone else may pipe in with an idea or two.

Do you know how long it takes for such a tree to die? or whether it is possible to check if it's recovering or not? How can I monitor the tree at this point? and how moist should I keep the soil? Do I cut off the leaf tips that have sustained damage?

 

[sorce]

No worries!

Welcome to Crazy!

If you lose, you ain't losing much!

Sorce

 

[Bonsai Nut]

I've managed to kill a few trees with chemical fertilizer. It isn't hard to do - just like it isn't hard to burn a spot in your lawn with chemical fertilizer. It isn't unusual for chemical fertilizer to be 10x stronger (by volume) than organic.

The damage is usually caused by the fertilizer salts preventing water uptake by the roots. The tree isn't so much "burning" as "drying out", and the damage appears similar to what you would see from sun overexposure or underwatering - even if the soil is wet. The only thing you can do is rinse the soil thoroughly with clean water, try to remove as much of the fertilizer salts as possible, and protect the tree in the short term from sun and wind (because it has compromised roots). I know it is too late, but in the future avoid repotting since that will just add more stress to the root system.

I wish you luck! Good news is that it is a small Japanese Maple and not an import Japanese White Pine like the one I killed with chemical fertilizer about 30 years ago. It was a lesson I never forgot By the time I realized I had a problem, the tree was already dead.

 

[VAFisher]

Oh and I don't think it's environmental damage because I also have 2 other maples that are doing super well. I did not feed those with the chemical fertilizer

Sounds like you have it figured out and dont need help. By the way, I fertilize my Maples with 15 9 12 osmocote pellets and a weekly dosage of 20 20 20 liquid fertilizer at 150% of the recommended dosage and my leaves are fine.

 

[MindMint]

Thank you all for your input. Should I start morning the tree or does it have a slight chance of recovery? and how can I monitor its health generally? and how much should I water it?

 

[Bonsai Nut]

Thank you all for your input. Should I start morning the tree or does it have a slight chance of recovery? and how can I monitor its health generally? and how much should I water it?

Keep the soil moist, but not wet. Treat it like a maple cutting that has no roots. Give it only indirect bright light (no sun) and protect it from wind. Keep it in a humid environment and mist the leaves. You want to slow down the rate of transpiration from the leaves while the tree attempts to grow new roots. It will take four-six weeks for a maple to grow some new roots, and even then it will have a weak root system for at least a full season.

 

[Forsoothe!]

I repot trees in full leaf in June, including JM. To me, raking out roots is more damaging than washing out and scissors cutting. The trees stay in indirect bright light until new buds begin to expand, then they go into the light appropriate to that species, which is no midday for JM between June 1st and August 15th.

There's no cure for stupid and we've all had some of that. Chemical death is usually displayed as the entire leading edges of leaves going brown, and total death showing as all brown leaves very suddenly and not falling off. Blotches on leaves don't seem to reflect this. The description details of over fert is absent, so we don't really know the details. Granules are designed take a while to break down, and liquids are immediate and absolutely unforgiving, so what we see pictured doesn't reflect either. So, we know nothing at this point except that there is no evidence of over-fert. Much ado about nothing.

 

[MindMint]

I repot trees in full leaf in June, including JM. To me, raking out roots is more damaging than washing out and scissors cutting. The trees stay in indirect bright light until new buds begin to expand, then they go into the light appropriate to that species, which is no midday for JM between June 1st and August 15th.

There's no cure for stupid and we've all had some of that. Chemical death is usually displayed as the entire leading edges of leaves going brown, and total death showing as all brown leaves very suddenly and not falling off. Blotches on leaves don't seem to reflect this. The description details of over fert is absent, so we don't really know the details. Granules are designed take a while to break down, and liquids are immediate and absolutely unforgiving, so what we see pictured doesn't reflect either. So, we know nothing at this point except that there is no evidence of over-fert. Much ado about nothing.

hey! thanks for the input when I washed out the old soil, there was still some organic fertilizer in it because the water that came out was brown, so I am very convinced its a fertilizer issue, but it might be something else also. Like I said, I have 2 other trees that are doing very well. Why do you suppose the condition of the leaves is still getting worse?

 

[Forsoothe!]

Newbees expect that all leaves should be perfect all the time. Shit happens. Birds crash into trees and lead with their viscous little claws, then they peck off bugs with beaks that they sharpen and de-burr on woody branches, squirrels investigate, possums and raccoons wander through pushing things aside, winds whip, bugs bite, caterpillar suck, and altogether there are more reasons for the leaves to get mechanically damaged than not. Pick off the leaves you don't like and forget about it, you won't notice the absent leaves after they're gone.

 

[MindMint]

It certainly doesn't look like mechanical damage to me, if it was mechanical damage it wouldn't have been all of the leaves that are affected anyway thank you for your input. I had already cut the leaves that look very bad, it didn't change anything in regards to the overall health of the tree... I guess I just have to wait and see what happens now given that there is really nothing else I can do besides the thing that I have done

 

[penumbra]

Do you know how long it takes for such a tree to die?

No easy answer there. If the trunk turns black its dead. Otherwise, it can be weeks or months. I just found a trident in my trash pile that never leafed out in the spring. Apparently it leafed out in the past few days.