Ulmus parvifolia rescue

[IamOrg]

Hello,

This little Chinese Elm is my first bonsai since my last disaster... I wasn't sure what title to give it or where to place this topic (I noticed there are already many "Chinese Elm" topics), so I hope I've found the right place.

So, first, a presentation/explanation, and then quite a few questions. I purchased this tree in a nursery in June 2023, labeled as a "Chinese Elm," and I placed it outside, northwest exposure (to be honest, I find that exposure doesn't tell you much; it had sun from 3 PM until evening).



First observations: I'm not sure which front to choose; the structure isn't great with big branches crossing each other, the base of the trunk is strange (probably because it's from a root cutting?), and it seems there's a huge root/trunk piece that's exposed at the surface of the soil.

I've given it a small basket of organic fertilizer and watered it when the top of the soil gets dry. In mid-July, I saw a lot of spider webs in the branches, so I sprayed anti-mite solution, but looking back, I think they were actually "real spiders" (I have plenty of them in my garden). It eventually produced a bright red bud, so I renewed the fertilizer in mid-July, and in mid-August, I gave it a foliar fertilizer application. There was quite a bit of rain in August, and I had a hard time deciding when to water because the top of the soil was always wet. A few days later, it started getting a lot of yellow leaves that eventually fell off. Not knowing the exact cause, I stopped the fertilizer, moved it to an east-facing position (sun until 2 PM), and soaked the soil for 15 minutes, and many bubbles came up.



Ten days later, lots of buds appeared. Since then, it's been growing, and I've resumed its fertilizer and soil soaking every 2 or 3 waterings. In retrospect, I think it got too hot or lacked water. The soil is probably compact, and water wasn't penetrating well (I know, it's a classic case, but of course, I thought I was smarter by seeing water go in a bit...).



It was doing fine with lots of buds after I soaked the soil. But I think I got worried and now I've overwatered it. I lost track with the rain, which only wets the surface of the soil, and I probably watered it too much as a precaution. How do you handle rain to determine when to water?

The old leaves gradually turned yellow, and now there are very tiny black spots on some leaves. My research suggests it's a fungus. So, I removed the most affected leaves (sorry forgot taking pics) and plan to treat it with copper mixture, even though I'll end up with a smurf-bonsai...

I'm a bit desperate and wondering about repotting this weekend (with or without bare roots, I don't know). The tree is in bad shape, so it doesn't seem ideal, but if the problem is the soil, it's a vicious cycle, and I see no way out; I have to break the cycle at some point.

What I don't understand is why it was doing well when I bought it if the problem really is the soil. It was indoors, and I have no idea how it was watered.

In short, I plan to repot it (slightly larger pot, 1:1:1 Akadama/pumice/lava rock) and prune it in the spring to move towards a broom style because it's a bit all over the place right now.

I have quite a few questions and concerns:
• Should I repot now?
• Is there anything I can do to improve the base of the trunk?
• What should I expect with this large exposed root?
• Is it normal for the buds to be red?

Thank you for taking the time to read this!

 

[dbonsaiw]

I wouldn't repot or really do anything now. Just try to nurse it back to health and get it ready for winter. If you are watering every few days, there's no need to also soak it. Rain is a funny topic for me. If it rains heavily, then no problem - I treat that as a watering. If the rain is light, I will water in the rain (my family stands at the window and laughs at me). This way I don't have to stress it.

It's a little hard to see in the pics, but roots can be cut back at the next repot and other buried, as appropriate.

 

[Michael P]

As long as the soil is still draining, even slowly, do not repot it now. Put a chop stick or wood dowel into the soil and leave it there. When you think it needs water, pull the chop stick out and look and feel the buried part. You can do this every day at first until you become used to watering properly. If it is moist, the tree does not need water. If it is dry or almost dry, water it.

In your climate (8b) the tree should stay outside all year round. It looks like it has been in that pot and soil for a LONG time. Keep it healthy over the fall and winter, then repot in spring just as the buds begin to swell. Show us pictures again in late winter.

Good luck!

 

[Shibui]

What I don't understand is why it was doing well when I bought it if the problem really is the soil. It was indoors, and I have no idea how it was watered.

It was probably doing well in crap soil because the original grower knew how much water to give for that soil type. Watering by the soil drying is the only way to go, whatever soil it is in. If you monitor the soil moisture and only water when it begins to get dry the tree should be fine. Learning how to do that well is the big issue.

Chinese elms are tough. They can be repotted any time of year in warmer climes but it seems to be safer to stick with spring repotting in cooler areas. If you were just to rake and wash out the original soil without chopping lots of roots I suspect the tree would recover well but there's always some degree of risk giving advice from the other side of the world without being able to see or feel the tree in person.
Your best option would be to try to manage the soil you have for the rest of Autumn and winter then repot in spring.
I have always agreed that if the soil is killing the tree then changing the soil is the lesser evil and should give it a chance however small. The question is whether it is the soil or your care that's causing the problems.

How do you handle rain to determine when to water?

Same as watering from the tap. If the soil is damp don't add more water. If the soil is starting to dry out it needs water. Need to check soil moisture below the surface for accurate results. A light rain may wet the surface and look OK but still dry inside where the roots are. On sunny days the surface may look dry but soil still wet below and not need water. Use finger to check below the surface or use a wood skewer/chopstick left in the soil to monitor soil moisture.

plan to treat it with copper mixture, even though I'll end up with a smurf-bonsai...

Copper fungicide will not turn the tree blue. Never has and pretty sure it never will.

• Is there anything I can do to improve the base of the trunk?

There are lots of things you can do to the trunk base. Severe root pruning at Spring repot could make a big difference depending what you actually have down there.
Layering is another option to start an entirely new root system above the existing roots then chop those off when the new roots are growing well.
Sometimes just tilting the trunk to expose other roots can even out an uneven root spread.
Really need to see what's there to work out what is possible and what may be better.

• Is it normal for the buds to be red?

Pink new leaves is normal for Chinese elm.

• What should I expect with this large exposed root?

You should expect the large root to stay larger than the others until you do something about it. You could work with it as a part of the tree or use a number of possible techniques to change the relative root sizes or replace it altogether.

 

[IamOrg]

Many thanks for answering each of my questions!

I owe you all an update. My poor tree lost few more leaves (yes that is possible...) from the fungus but it is now somewhat stabilized. Here is the skinny chicken now



I am planning on spring repotting and installing it in my tiny winter greenhouse when night temperatures will drop.

Fingers crossed it survives