noobie with a sick elm

[phil_sheridan]

Hi everyone,
I'm new to this forum, I have a ulmus that I purchased about four years ago from an online business in Florida,it's my only bonsai, I have previously killed a mallsai though. The elm his been a very forgiving tree, and I have been most happy with it. I am in zone 6, and ignorance being bliss, I have over wintered the tree in my house. It has always looked quite shabby in the spring, I have been putting it out in April and it has always lost its leaves and re-foliated. I repotted it 18 months ago, to a little larger and better looking pot, I used commercial garden store potting soil. Last year was like previous years, and I brought the tree in to over winter. Over last winter it shed all of its leaves in midwinter, and leafed out again in midwinter. The leaves were much smaller than in any previous year, and very dark green. I put the tree out this spring as always. It lost all its leaves again, (oh no), and put on very small dark green leaves again. I am worried now, I think the tree is trying to tell me I'm killing it. I have a real fear that I'm going to kill the tree. My thought now is that I want to pull it out of the pot and see if it is root bound, but if I understand at least some of what I have read on the forum, this is the wrong time of year. So, right now the tree has over small dark green leaves, and I am looking for some inputs before I get real stupid and thrash about...would it be a good idea to pull the tree and repot? if so what type of soil? I've been using miracle grow...should I be looking for a better chemistry? Any and all comments and advice are much appreciated, ...phil

 

[iant]

I would wait until spring to repot. I think at that point you should get rid of the potting soil and change to a bonsai soil. There's lots of info on this site and others about bonsai substrates (soil.) They're all faster draining than potting soil. For now I would just not water it unless the soil is dry 2 inches below the surface (you can stick your finger or a chopstick in to test.)
I'd also consider leaving it outside for the winter. I'm in coastal California so I'm not the biggest winter expert but I think Ulmus Parvifolia should be okay in zone 6 outside. You could protect the pot a little with mulch in the winter (others could advise you on this) or bring it into the garage for the coldest spells in the winter but it's probably better outside having a normal winter. As you have it now it's getting signals to grow and then not and then grow and then not. It's tough on a plant to not have clear growth cycles.
Ian

 

[iant]

One more thing... I wouldn't be too worried that you've done irreparable damage. Ulmus are very resilient. If you give it a little winter and you repot it in nice bonsai substrate in the spring and give it good sun it will likely take off and do great.
Ian

 

[JudyB]

Iant is right on the nose with his advice. But even when you keep elms in the correct condition, they can and will self shed their leaves sometimes during the growing season. Mine turn over their leaves a couple times a year. But giving the tree a dormancy break during the winter is important, so it does not exhaust itself. Although I have heard of people that have kept them happy inside, I have not had that experience. For dormancy it's best to keep it somewhere it'll stay between 25 and 40 degrees, like an unheated garage, or if you do keep it outside, (I don't know what your winters are like), you can bury the pot in the soil, and mulch it in overwinter. Your tree will not need any light during this dormancy period. Don't water when it's frozen, keep it moist but not wet... If you get snow, just shovel the snow over top of it, and you're golden!

 

[phil_sheridan]

Thanks for all the input. A normal winter here will have a couple of Arctic fronts that will bring maximums under 20f, mins of -0f, occasional winters bring -10F or so. Historic records are around -20f. Most winters are very dry from November through the end of January. Normal fall will bring a freeze in October, occasionally late September, last year it was November. I guess what worries me most is the leaves are only about half as big as 'normal', and a very dark green. ( feel kind of weird to whine about the leaves being too small) I over winter my dahlia tubers in my unheated attic, they need cold, but not freezing cold. Could this regimen be cold enough to give the tree its dormancy?..
Thanks again,
Phil

 

[JudyB]

Don't worry about the leaf size, it's just because it self defoliated, and the second flushes are normally smaller. I would worry about the tree breaking dormancy in the attic, as all the heat on a sunny day will collect up there. Also it'll be out of sight, (and out of mind) and you will not be checking it to see if it needs watered, or to make sure the mice aren't nibbling at it...

 

[phil_sheridan]

Hi all, been offline a couple of days. Here is a link to a photo of my leaves, I used a U.S. penny for scale.....sorry I didn't have an imperial/metric scale handy, anyway the leaves are about 1/3 size of what it used to be.
Drop box link of photo:

http://db.tt/HqbNSuMF




Phil

 

[Zach Smith]

Phil, as others have noted you've done a couple things wrong with your elm. Overwintering should never be inside for an elm (any elm). And regular potting soil usually spells death for bonsai. The other thing to bear in mind is that you've probably weakened your tree over the past couple of seasons, so it's going to need time to recover. With good bonsai soil and proper overwintering, I'd then let the tree grow out for an entire season without any significant trimming, to regain strength. Feed lightly to begin the next growing season, then if you see strong growth coming on go ahead and feed heavily for the remainder of the year.

Good luck!

Zach

 

[jk_lewis]

One more thing... I wouldn't be too worried that you've done irreparable damage. Ulmus are very resilient. If you give it a little winter and you repot it in nice bonsai substrate in the spring and give it good sun it will likely take off and do great.
Ian

And do NOT over water. Let the soil dry all the way though before watering! That nursery soil holds a lot of water.

 

[phil_sheridan]

spring update

Hi,
I left my elm out all winter. We had a normal dry winter, I watered it a few times. It was buried in leaves at the base of a south facing retention wall. The temperatures were seasonable, many freezing nights, over night lows as low as 6 degrees F,some daytime highs in the low 20'sF. The elm started to show signs of life a few weeks ago. I read the repotting guides at http://www.bonsai4me.com/bonsai_basics.html, and found some quick drain soil with akadama at bonsai trees.com.
The temps have been in the 60-70 F range and the buds started to show green tips. I repotted today. The weather is going to be rough for a couple of days , so the plan is to keep it inside until Thursday or Friday unseasonable cold 24F lows are expected.
I trimmed the roots a little, and washed out all the old soil. I left some surface roots, I didn't know what else to do with them.I am going to load a couple of pictures. The tree needs a trim, but probably after it recovers.

Pics :
http://db.tt/klnsh2AM
http://db.tt/3S6KEvjt
http://db.tt/77pZphTT