Chinese Elm Overwatering Accident

[apizzimenti]

Hello all – I am in need of some specific advice.

A bit of backstory: I have had a chinese elm bonsai for about six months. It was ~5 years old when I received it (as a gift), although I am experienced in indoor gardening, have done my homework on the chinese elm, and have cared for other bonsai quite successfully in the past. I live in Washington, DC and keep my chinese elm in an extremely bright south-facing window (with a grow-light for dimmer days) in a humid room in the apartment; it has an appropriately balanced soil mixture, I water when needed, and generally just give the tree as much space as possible to grow healthily. It grew quite a bit over the summer and into the early fall and, as expected, leaves began to drop for the winter en masse about last week when the lowest-light and coldest days started to hit. Leaf loss and less growth aren't my concern here.

Last night, my partner and I were preparing to drive home for the holiday, and I watered some of my houseplants and my bonsai at the same time using a simple method: place the potted plants into a tub and fill the tub until the bottoms of the pots are completely submerged, and let the plants take up the water they need. I've used this method somewhat regularly when my plants' individual watering schedules line up nicely or I need to give them all some water at the same time. Well, in the hustle to finish packing, I left the plants in the tub not for ~30 minutes, but for a few hours. Once I finally remembered and went to check on the plants, I immediately noticed the leaves of my tree blackening, when they'd been green only an hour before. (In the images below, all the blackened leaves were completely green. These pictures were taken ~30 hours after I removed the pot from the water.)

While I'd like to think that I know what to do, I don't. And I'm panicking. So, to help figure out what to do, I have a few questions:

1. Are these effects the result of overwatering? (My guess is yes, but any more detail would be greatly appreciated.) I noticed (as in the second image) that there is some white splotching on some of the leaves – what is that, and is it possibly causing this problem?
2. What do I do? I have seen an incredible number of online sources telling me how to diagnose overwatering, but very few on how to treat it. As of now, I've moved the tree to a very dry room during the night to try to remove moisture from the soil.
3. How can I prevent this from happening again? I understand that "don't waterboard your plant for hours" is an obvious answer, but is this the result of overwatering that's been taking place for a long time? Why hasn't my tree shown symptoms like this before when I've watered it in a similar manner?

I greatly appreciate any advice, and am thankful to all the posts on here that have helped guide me through bonsai care for the past few years. You all are amazing and I am open to any suggestions, criticism, advice, or wisdom you can share to help me save my tree.

Thank you!

 

[LittleDingus]

Hello all – I am in need of some specific advice.

A bit of backstory: I have had a chinese elm bonsai for about six months. It was ~5 years old when I received it (as a gift), although I am experienced in indoor gardening, have done my homework on the chinese elm, and have cared for other bonsai quite successfully in the past. I live in Washington, DC and keep my chinese elm in an extremely bright south-facing window (with a grow-light for dimmer days) in a humid room in the apartment; it has an appropriately balanced soil mixture, I water when needed, and generally just give the tree as much space as possible to grow healthily. It grew quite a bit over the summer and into the early fall and, as expected, leaves began to drop for the winter en masse about last week when the lowest-light and coldest days started to hit. Leaf loss and less growth aren't my concern here.

Last night, my partner and I were preparing to drive home for the holiday, and I watered some of my houseplants and my bonsai at the same time using a simple method: place the potted plants into a tub and fill the tub until the bottoms of the pots are completely submerged, and let the plants take up the water they need. I've used this method somewhat regularly when my plants' individual watering schedules line up nicely or I need to give them all some water at the same time. Well, in the hustle to finish packing, I left the plants in the tub not for ~30 minutes, but for a few hours. Once I finally remembered and went to check on the plants, I immediately noticed the leaves of my tree blackening, when they'd been green only an hour before. (In the images below, all the blackened leaves were completely green. These pictures were taken ~30 hours after I removed the pot from the water.)

While I'd like to think that I know what to do, I don't. And I'm panicking. So, to help figure out what to do, I have a few questions:

1. Are these effects the result of overwatering? (My guess is yes, but any more detail would be greatly appreciated.) I noticed (as in the second image) that there is some white splotching on some of the leaves – what is that, and is it possibly causing this problem?
2. What do I do? I have seen an incredible number of online sources telling me how to diagnose overwatering, but very few on how to treat it. As of now, I've moved the tree to a very dry room during the night to try to remove moisture from the soil.
3. How can I prevent this from happening again? I understand that "don't waterboard your plant for hours" is an obvious answer, but is this the result of overwatering that's been taking place for a long time? Why hasn't my tree shown symptoms like this before when I've watered it in a similar manner?

I greatly appreciate any advice, and am thankful to all the posts on here that have helped guide me through bonsai care for the past few years. You all are amazing and I am open to any suggestions, criticism, advice, or wisdom you can share to help me save my tree.

Thank you!


View attachment 345282View attachment 345283

I have no direct experience with Chinese elm so hopefully others will chime in shortly.

What I will say is rarely will a tree sitting in water for "a few hours" harm it. What I will also say is generally leaf discoloration from everwatering is yellow and not black.

Black is usually more indicative of fungal issues. But, in your case, judging from the pictures, I have to wonder if maybe your grow light is a spot light variety and maybe puts out a lot of blue? I wonder if maybe you're burning chlorophyl?? It looks like most of the top leaves are discolored and, around near the bottom ones that still look good, I see some that are discolored on an edge only.

Don't panic until smarter people than I tell you too But I don't think the issue is a few hours of water...

...and welcome to the forum

 

[Bonsai Nut]

Welcome to the site!

When diagnosing problems with your elm, it is important to look at where the symptoms are showing up, and how they are spreading. For example, sun or light scorching will affect the outer and upper leaves first, insect damage will typically be localized and may be accompanied by physical damage, etc. In this case, when inner leaves rapidly start to die, and then the problem spreads to the outer leaves, it is usually the sign of root problems. The black leaves suggest fungal issues... but whether the fungus is causing the problem, or whether it is just taking advantage of a situation where the roots have died, it is hard to say. Given that you have never had black leaf problems before (prior to soaking the tree) I'll assume the later.

If the roots are compromised, your tree is going to be struggling to get enough water. Ironically, the solution is NOT to water the tree - which will simply exacerbate the problem with the roots. Instead you want to slow down the rate of transpiration in the leaves by putting it in a very humid environment. If you have a mini-greenhouse (like for houseplants) that will work. Even something as simple as creating a humidity tent out of a clear plastic bag will help. You want to continue to provide light so the tree can photosynthesize. If you can spray the leaves with water (without soaking the soil) it will also help. As far as the soil goes, make sure it is draining freely through the drain holes in the pot. Try to do this physically (instead of by watering the tree) by probing the soil with a chop stick or similar. For the next few weeks, you want to protect the foliage and keep the soil from drying out... but you want it barely moist and not wet or saturated. You will know you are out of the woods when/if the tree starts to push new buds.

In the future, never water a bonsai from the bottom up. Always water the top of the soil until water is running freely out of the drain holes. With an indoor tree, if you have decent tap water and a kitchen sink sprayer, you can set the tree in your sink, spray it, and let it drain in the sink before you move it back to your growing area. If you have more / larger trees and you have a hand-held shower sprayer, you can set all your trees in the shower and spray them there. Roots need oxygen in order to survive. If you set the tree in standing water you are drowning the roots. In some cases you might not notice the damage, and you just have a tree that appears weak and sickly. In other cases, in can be pretty severe. Otherwise... make sure you only water the tree when it is needed. Make sure the top of the soil is almost dry... just barely damp... before you water again. Having recently moved to North Carolina, I have a number of tropical species that cannot stay outside year round. I have them sitting indoors in a sunny area. When I want to water them, I take them outside on a day when it is above freezing, water them thoroughly with a garden hose sprayer attachment, allow them to drain, and move them back indoors. Even tropicals are almost fully dormant at this time of year, so their water needs are usually pretty minimal.

 

[Zach Smith]

For what it's worth, I'd say your Chinese elm exhibited, rather suddenly, a protest of conditions it has survived since you got it that were exacerbated by drowning the roots. Chinese elms prefer to be outdoors - period. They can survive indoors, there's no doubt about it, but they prefer to be outdoors as do all of the other plants that exist. Now that winter is here, your tree is not moving much water and is in a sort of dormancy. You don't indicate whether or not the soil was dry when you put it in the tub - but regardless, it certainly didn't need the amount it was offered. Roots need air, along with water. By submerging them for hours, you suffocated them. This is going to be hard for the tree to overcome in winter, the 2020 growing season being behind us; it will have to survive until the beginning of the 2021 season (or an early warm snap, see below), and that's a tall order. As for the black leaves, I'm not convinced it's fungal. Even if it is, it's not the problem here; the suffocation of the roots is the problem.

What to do? If you have an outdoor space, and your temps aren't going to go below 25F or so, put the tree outdoors (now or when you return; sooner is better). It will appreciate the rains when they come; your municipal water is almost certainly high pH, and most trees don't like that a bit. The rain will also provide air to the root zone, as the draining water will draw air in and that's just what you want. Any warm snap you have early next year is likely to cause this tree to bud out - this will be a good thing, but you'll need to keep on top of the weather and protect from freezing as needed.

I hope this helps. Good luck with your tree!

 

[sorce]

Welcome to No More Home for the Holidays!

Welcome to Crazy!

An indoor tree is a wee bit confused at least, even healthy. Perhaps it is just going dormant. Could be the water told it to go to sleep.

Definitely not overwatering, or root rot, though that pathogen can likely travel easier to other plants through bin watering.

Sorce

 

[apizzimenti]

I have no direct experience with Chinese elm so hopefully others will chime in shortly.

What I will say is rarely will a tree sitting in water for "a few hours" harm it. What I will also say is generally leaf discoloration from everwatering is yellow and not black.

Black is usually more indicative of fungal issues. But, in your case, judging from the pictures, I have to wonder if maybe your grow light is a spot light variety and maybe puts out a lot of blue? I wonder if maybe you're burning chlorophyl?? It looks like most of the top leaves are discolored and, around near the bottom ones that still look good, I see some that are discolored on an edge only.

Don't panic until smarter people than I tell you too But I don't think the issue is a few hours of water...

...and welcome to the forum

Yeah – I wrote this post after having driven halfway across the country and it does make sense that this is a response to an underlying issue present for some time rather than one that cropped up from just one watering.

To your question: my grow light has two lighting modes including a red/blue mode, but I rarely use it: it's not especially aesthetically pleasing, doesn't do much more to help the tree than day-long sunlight does, makes my neighbors think I'm growing weed in my apartment, etc. One of the responses below agrees with your assertion that black is usually a fungal issue, but I (try to) make sure the soil is nearly entirely dried out between full-soak waterings, but I have never been sure as I may have been reading the "yellowing to browning leaves" sign as underwatering, not overwatering and have been overwatering the tree this entire time.

Thank you for welcoming me to the forum! Hopefully my time here is less of this and more of learning + advice-giving in the future, but I am excited to be a part of it nonetheless. Also jesus christ you all respond quickly – I was expecting to wait days, not hours!

 

[apizzimenti]

Welcome to the site!

When diagnosing problems with your elm, it is important to look at where the symptoms are showing up, and how they are spreading. For example, sun or light scorching will affect the outer and upper leaves first, insect damage will typically be localized and may be accompanied by physical damage, etc. In this case, when inner leaves rapidly start to die, and then the problem spreads to the outer leaves, it is usually the sign of root problems. The black leaves suggest fungal issues... but whether the fungus is causing the problem, or whether it is just taking advantage of a situation where the roots have died, it is hard to say. Given that you have never had black leaf problems before (prior to soaking the tree) I'll assume the later.

If the roots are compromised, your tree is going to be struggling to get enough water. Ironically, the solution is NOT to water the tree - which will simply exacerbate the problem with the roots. Instead you want to slow down the rate of transpiration in the leaves by putting it in a very humid environment. If you have a mini-greenhouse (like for houseplants) that will work. Even something as simple as creating a humidity tent out of a clear plastic bag will help. You want to continue to provide light so the tree can photosynthesize. If you can spray the leaves with water (without soaking the soil) it will also help. As far as the soil goes, make sure it is draining freely through the drain holes in the pot. Try to do this physically (instead of by watering the tree) by probing the soil with a chop stick or similar. For the next few weeks, you want to protect the foliage and keep the soil from drying out... but you want it barely moist and not wet or saturated. You will know you are out of the woods when/if the tree starts to push new buds.

In the future, never water a bonsai from the bottom up. Always water the top of the soil until water is running freely out of the drain holes. With an indoor tree, if you have decent tap water and a kitchen sink sprayer, you can set the tree in your sink, spray it, and let it drain in the sink before you move it back to your growing area. If you have more / larger trees and you have a hand-held shower sprayer, you can set all your trees in the shower and spray them there. Roots need oxygen in order to survive. If you set the tree in standing water you are drowning the roots. In some cases you might not notice the damage, and you just have a tree that appears weak and sickly. In other cases, in can be pretty severe. Otherwise... make sure you only water the tree when it is needed. Make sure the top of the soil is almost dry... just barely damp... before you water again. Having recently moved to North Carolina, I have a number of tropical species that cannot stay outside year round. I have them sitting indoors in a sunny area. When I want to water them, I take them outside on a day when it is above freezing, water them thoroughly with a garden hose sprayer attachment, allow them to drain, and move them back indoors. Even tropicals are almost fully dormant at this time of year, so their water needs are usually pretty minimal.

Thank you, and thank you for such a thorough response. Having someone not panic in the face of this issue is calming, to say the least.

I will admit that part of the reason I have been so thoroughly freaked out is that I've never experienced black discoloration before, even with this tree. However, LittleDingus (in the above comment) noted that one of the symptoms of regular overwatering is yellowed leaves which then fall off, and I have experienced that with this tree before; sometimes, new growth is a much paler green than I'd expect as well, so I suspect now that I've probably been habitually overwatering this tree. In any case, it does make sense that I've drowned the roots, and I have no intention of ever ever watering trees like this in the future. Since I live in a fairly urban environment and don't have access to any real gardening equipment, I still do full soaks when the soil gets dry enough (although now I need to change my definition of "dry enough") where I fill up the sink or a large pasta pot and submerge the tree up to ~1in above the soil and wait for most of the air to escape the soil, then let the pot drain freely into a sink and replace it in its normal spot.

Thank you for providing some concrete steps for me to take to help my tree get better. I understand that there are no guarantees, but I've pulled off some miraculous plant recoveries before, so fingers crossed this one works out as well. I have a few questions:

1. Some of the inner foliage hasn't been completely discolored and is still green. Are these the leaves I need to protect the most? Are there any warning signs I should look out for that things aren't going right?
2. How large of a tent should I make? Just enough to envelop the tree itself, or one that wraps around the whole pot as well?
3. If you had to guesstimate, how long should I expect to wait before seeing new growth? Even up until ~last week the tree was budding and producing new leaves at a comfortable rate, but this is the most difficult thing I've ever faced with a bonsai tree and I have a feeling I'll be watching the tree like a hawk.

Again, thank you for your help, and I'll make sure to keep you all updated!

 

[apizzimenti]

For what it's worth, I'd say your Chinese elm exhibited, rather suddenly, a protest of conditions it has survived since you got it that were exacerbated by drowning the roots. Chinese elms prefer to be outdoors - period. They can survive indoors, there's no doubt about it, but they prefer to be outdoors as do all of the other plants that exist. Now that winter is here, your tree is not moving much water and is in a sort of dormancy. You don't indicate whether or not the soil was dry when you put it in the tub - but regardless, it certainly didn't need the amount it was offered. Roots need air, along with water. By submerging them for hours, you suffocated them. This is going to be hard for the tree to overcome in winter, the 2020 growing season being behind us; it will have to survive until the beginning of the 2021 season (or an early warm snap, see below), and that's a tall order. As for the black leaves, I'm not convinced it's fungal. Even if it is, it's not the problem here; the suffocation of the roots is the problem.

What to do? If you have an outdoor space, and your temps aren't going to go below 25F or so, put the tree outdoors (now or when you return; sooner is better). It will appreciate the rains when they come; your municipal water is almost certainly high pH, and most trees don't like that a bit. The rain will also provide air to the root zone, as the draining water will draw air in and that's just what you want. Any warm snap you have early next year is likely to cause this tree to bud out - this will be a good thing, but you'll need to keep on top of the weather and protect from freezing as needed.

I hope this helps. Good luck with your tree!

Thank you so much for your assistance.

To your point, it had been a little more than a week since the tree's last full soak, so I made the (rather poor) assumption that it'd be alright with getting one more watering. I probably should have waited until we'd made it to our destination since I brought the tree with me, but I wanted to make sure I had all my boxes checked. That being said, your diagnosis seems pretty spot-on, and I'll take it that as the cause of the leaf discoloration. Fortunately, there are still some buds on the tree (including one green one, which I'll keep an eye on), so I am somewhat hopeful.

Anyway, judging by the other responses in this thread, it seems like root suffocation is probably the culprit here. I'll be at my parents' home for the next two weeks (we are being covid-safe: we all work from home, have been isolating, etc.) and they have a bright, cool(ish) front room where I've placed the tree inside a little clear humidity tent, as Bonsai Nut suggested in one of the above responses. I live in a pretty urban environment and in a third-floor apartment, so I'll to fashion a window-hanging planter box of some kind to get it outside once the weather warms up. I also typically use filtered water to water the plants, so hopefully that isn't as much of an issue. I also recognize that these trees tolerate being indoors, but will thrive outside, and I understand that we are the stewards for these living beings and should care for them to the best of our ability; unfortunately, right now, I can't give it the outdoor care it deserves, so indoor care will have to suffice. Hopefully we'll be able to get a place with a nice outdoor space soon enough, but for now, I'll have to give this a go indoors.

 

[apizzimenti]

Welcome to No More Home for the Holidays!

Welcome to Crazy!

An indoor tree is a wee bit confused at least, even healthy. Perhaps it is just going dormant. Could be the water told it to go to sleep.

Definitely not overwatering, or root rot, though that pathogen can likely travel easier to other plants through bin watering.

Sorce

Thank you! I do understand that my tree is – and has likely been – confused since it came into my care, but I do my best to make sure it's on the straight and narrow. Don't want it to stray too far

Anyway, the timing of this was exceptionally unfortunate as the tree has been entering its little dormancy period and dropping its leaves over the past week. I don't expect the period to last super long, but I'll stay away from bin watering and keep an eye on the leaves for the next few weeks. Hopefully the extra light and humidity help it to bud out!

 

[Zach Smith]

Thank you so much for your assistance.

To your point, it had been a little more than a week since the tree's last full soak, so I made the (rather poor) assumption that it'd be alright with getting one more watering. I probably should have waited until we'd made it to our destination since I brought the tree with me, but I wanted to make sure I had all my boxes checked. That being said, your diagnosis seems pretty spot-on, and I'll take it that as the cause of the leaf discoloration. Fortunately, there are still some buds on the tree (including one green one, which I'll keep an eye on), so I am somewhat hopeful.

Anyway, judging by the other responses in this thread, it seems like root suffocation is probably the culprit here. I'll be at my parents' home for the next two weeks (we are being covid-safe: we all work from home, have been isolating, etc.) and they have a bright, cool(ish) front room where I've placed the tree inside a little clear humidity tent, as Bonsai Nut suggested in one of the above responses. I live in a pretty urban environment and in a third-floor apartment, so I'll to fashion a window-hanging planter box of some kind to get it outside once the weather warms up. I also typically use filtered water to water the plants, so hopefully that isn't as much of an issue. I also recognize that these trees tolerate being indoors, but will thrive outside, and I understand that we are the stewards for these living beings and should care for them to the best of our ability; unfortunately, right now, I can't give it the outdoor care it deserves, so indoor care will have to suffice. Hopefully we'll be able to get a place with a nice outdoor space soon enough, but for now, I'll have to give this a go indoors.

I think you have a good plan. Filtering your water is fine, but it won't change the pH. Consider using a soil acidifier, or watering with vinegar water every four weeks or so (a ratio of 1 tbs distilled vinegar per gallon of tap water usually works well).

 

[apizzimenti]

Hello everyone – I have some good news! It's been exceptionally sunny and warm enough in my parents' house to provide good recovery conditions for my tree, and it's shown two new buds (!!!!) since last night. I was a bit worried for a bit and it's going to be incredibly cold the next few days, but my tree seems to be doing alright for now.

Again, thank you for all the help you've provided me. I'm so grateful for your calming wisdom and sage advice – you've saved me quite a bit of heartache. I'll certainly return to ask more questions if I have them. Thank you