cedar elm question

[DaveV]

Does anyone have experience with cedar elm as bonsai? I live in Iowa (zone 5) and am concerned about overwintering. I keep all of my trees in an unheated attached garage during the winter and it can get down to 25 F in the dead of winter in the garage. Is this too cold for cedar elms? Can their roots freeze in the winter? Are they susceptable to any particular disease? Are there any other concerns (branch die back, easy root rot, ect.) that I would need to know about for potential bonsai culturing ? Thank you!

Dave V.

 

[rockm]

I have kept large cedar elm (and this can make a difference in overwintering) outside under only mulch here in Zone 7 Northern Va. I've had temps down to 0 F in the past. The bigger tree (5 inches at the nebari, 3' high in a pot that holds about 4 gallons of soil, has had no problems whatsoever in the last 10 years with this. I had a smaller tree in a smaller pot, however, that eventually died.

I'd say, if the temperature goes below 25 or so in the garage, you'd probably be OK with putting the tree on the floor and mulching it over with eight inches of shredded pine bark mulch.

A rule of thumb--the smaller the pot, the more protection. Trees in larger containers tend to survive low temps than those in smaller containers. Soil mass can provide alot more buffer against temperature extremes.

 

[treebeard55]

Good points, Rock.

I've considered keeping cedar elm here in IN, also zone 5. My understanding is that they are half-hardy here, like JBP (when potted) and trident maple. Leaving them with other fully-hardy trees means death; they need some special protection.

My suggestion would be a coldroom, where the temperature stays in the upper 30's and low 40's without freezing. That's what I'll do if I ever get a cedar elm.