Catlin Elm in hot dry AZ. Help!

[AZ Newb]

Hello from beginner in sunny, hot and DRY Phoenix, Arizona. I am struggling with my Catlin Elm. More and more brown and dry leaves. I’m starting to lose some fine branching as well. I had been watering in the early evening. I was worried about watering in the morning, as I thought the wet roots in over 110 degree dry heat would “boil”?? I’m starting to water morning and evening to see if that might help. Please see pics below and if anyone would be kind enough to share any thoughts, I would greatly appreciate it. Full disclosure: I did not do the hard work on this tree. I joined the Phoenix Bonsai Society and bought it in the club auction. I really have no business owning a tree like this! Just wanted something nice around all the training trees that I am learning on. The first pic is from a week ago and next 2 are from today.

 

[Boris]

Hi. Here in NM (12000ft so not as hot as in AZ), I put my elms in the mid day/afternoon shade and water them twice. Don't worry about 'boiling', the evaporation cools down the plant. I've seen that even after one or two days in the 90's my elms start loosing all the leaves just to come back 'happy' after a while. I think I can see little buds coming already in your tree.
Probably mist, can take heat from the surroundings and help cool down the tree. Good luck

 

[ihaveaspaceship]

you can put a finer partical mix as a top coat to retain more moisture. like 1/8th -1/16th.
That or maybe add some sphagnum/moss to the top.

 

[atlarsenal]

I put my elms in the mid day/afternoon shade and water them twice.

@Boris said I right there. 3 times a day isn’t going to hurt it.

 

[bonsaichile]

If you got it at your club, perhaps the best thing you can do is ask the person you got it from how to care for it in your particular weather. The info they can give you will beat anything we can tell you here.

 

[AaronThomas]

Hey! Nice to see another Arizona resident in the nut house!
SO I water my Elms mid morning... and really soak um'. Never had the boil issue. This time of year ill water them again late afternoon. (probably don't need to though) IF you can't keep the substrate moist you can put down an inch or so of sphagnum moss down on top... I use wire around the pot to hold in place as the dry winds will blow it around as it drys out.
One of my trees went a bit crispy this year as well. Just soaked it and kept in shade for a few days. If its a drought thing it will bounce back with a little care. Looks like you have buds popping already in the second pic.
PS
What is the substrate? Looks like lava, pumice and bark?

 

[AZ Newb]

Thanks to all for the great ideas! I really appreciate your time in replying to me. I’ll post a follow up pic if it survives the summer.

 

[Smoke]

Set it under the patio table or chair. Water as usual. Keep it out of the sun and don't do a wet area under it to try and cool it down. You will just set yourself up for fungus next.

 

[Captain.Bonsai]

It needs sun for photosynthesis but clearly too much sun and heat can damage it. First, filter the sun it’s getting with a shade cloth if u haven’t already (I have also found that heavy duty fiberglass sliding screen door material is cheap and effective in small areas. Amazon has them for $10 or so).

Next, insulate and subsequently cool the elm substrate... Get a larger pot of similar depth that has adequate drainage - plastic training pots are good because they usually have ample drainage. Place the elm pot in that empty pot. Then surround the smaller pot with mulch or bagged potting soil. U don’t need to cover the substrate of the elm, just fill the bigger pot to the height of the elm pot. Don’t put any soil or mulch under the elm pot, it needs to drain. Then water all of it as needed according to the elms substrate moisture needs.

It’s all about the heat lately. These methods work for me.

 

[Boris]

I also put them on top of a larger pot with standard soil, it acts like a buffer for water