Uh-oh, Chinese Elm waking up!

[sfhellwig]

Last year I did quite a few seeds, largely maples to create a bunch of cheap stock to work on. I used palettes to build small shade structures that have also been used as winter protection, being wrapped in translucent plastic. Most of my Chinese Elm seedlings didn't do too well so I left them out right next to the "huts". Two or three did make it in. We have had a cold and snowy winter (most of you know what I am talking about). So this weekend we were supposed to have some ridiculously high temps. Trying to be smart I cracked open the flaps on the two huts so they woldn't super heat. Over the weekend I noticed the daffodils and surprise lilys were starting. As I am about to batten down the flaps on the huts I figured I should check for watering and low and behold, there is green at the tip of a CE. This is not what I would expect as we haven't had any extended periods of warmth. Either way, this tree will have to be brought in now, right? No two ways about it.

If dormancy is broken, it can't get frozen. At least I can probably slide it in at work where we keep approx. 50% humidity. Otherwise I would not expect it to leaf out and live in the home environment. My house is bad on humidity and we are still nearly three months from our frost date. There would be no healthy way to bounce it indoors on freezing nights and outside for the rest of the time. So I just wanted to get confirmation on the sad truth. It's bring it in and cross my fingers. I just can't get the early start. Perhaps my huts have stayed warmer than I thought but we just thawed off a record snow. Daffodils have to push for a fair bit before breaking ground. It seems the harder the winter the sooner and harder things want to pop back. But the bulbs have had no real cue to do what they are doing.

 

[rockm]

What do you mean by "green at the tip?"

 

[sfhellwig]

I mean like buds breaking. Not just a green twig. I was going to close up the huts at lunch but figured I might need to water a little. I looked in and it happened to be right near the front edge. Appears to be apical buds breaking. Of course that's the first thing I will look at when I get home, I guess I'd better make sure it wasn't critters. I had noticed several green shield bugs over the past few days.

 

[rockm]

Have they broken open--lead edges standing away from the bud, or are they just green and fat? It's an important distinction...

 

[sfhellwig]

I was thinking you were the one I saw mentioning that to someone else. I guess last year I mostly just looked at maple buds so I saw green and was certain they were open. I'm not sure what post you described it so well in but the distinction is the leaf edge, touching or still held tight? I was waiting to see the forecast before I went and closed everything up. Doesn't look like any of the maples are bothered. However, half the flat of mimosas outside of cover look like they have already broken and have tiny leaflets about to unfold. I can put them in the garage but that won't be safe from every thing that will still come this winter. I thought they were some of the last to wake up. Everything is really off here.

 

[Bill S]

"I used palettes to build small shade structures that have also been used as winter protection, being wrapped in translucent plastic."

The plastic was probably the culprit, really should be the white opaque type, it's probably quite a bit warmer in the cold frame than you want it.

 

[sfhellwig]

I was contemplating that last night. Thought about black and then realized that would turn into an oven. I need to find something to put over the top for more shade, considering the tops were about 50% to start. I'm sure it's too late now anyway unless to stay off the maples. While my structures avoided winter die back due to wind, their small size likely makes the temperatures fluctuate far more than a hoop house. I was so worried about the huts barely helping, I sure didn't expect them to work against. I guess I'd better really start keeping them open more often than not. I looked at my garden log and realize the flowers aren't really off, we have just been thoroughly winter up till this weekend. About two weeks ago or so they were buried half way up in snow and the plants were already thinking about waking up. We had TWO DAYS of high temps.

I did bring the CE in last night to inspect the buds. That was fun. I don't have a proper magnifying glass so it was reading glasses and a 10x loupe, hovering around the bud until I could get it in focus. Everything looked great, just a couple of fat green buds until I found the tiniest leaf. Barely discernible but it had a point and serrated edges. But no matter how small, this would denote a broken bud. I was so frustrated with that and the mimosas looking like they had opened that I just put it in the hut and closed them up. We were supposed to have 24 last night. The plastic would keep the frost at bay and no freezing for the next week right now. I will just have to inspect and see what happened. If the elm appears to continue opening I will have to bring it in the next freezing night. I may already have several dead plants.

And the lesson goes on.

 

[sfhellwig]

Thinking about the original purpose of the huts, they were to avoid the worst of the winter. Should I remove the front flaps and leave the trees open to the air to avoid further overheating? Anything still sleeping will be fine unless we have any serious lows, at which point I could button them up for the night. Is this a proper line of reasoning to avoid further issues?

 

[Dav4]

Is this a proper line of reasoning to avoid further issues?

Yup...

When I overwintered trees in my unnattached garage in MA, I routinely noticed the mid to late February sun was strengthening to the point where it was causing daytime temps in the garage to routinely roll into the 50s or higher, even if outdoor temps stayed in the 30s. Leaving the doors open was one way to avoid too much heat gain during the day. Honestly, unless it was due to get extremely cold, I would leave the doors atleast partially open at night as well. The colder the better to keep things dormant.
Assuming the buds are not actually opening but have just started to swell. I think your elm will be fine as long as the rootball doesn't freeze solid from now on. Maybe you could mulch the pot in your enclosure. To transition my maples outside, I used to take my maples out of the garage (they were mulched in on the floor) and mulch them into my garden as soon as I saw any bud swelling, usually in mid/late march. Obviously, the canopy would be exposed to frost for another 6 weeks, but the mulch kept the rootball from freezing, and the trees did fine. Good luck,

Dave

PS get a min/max thermometer for next winter. It helps get a handle on what's really happening tempwise in your enclosure.

 

[rockm]

If the edges are not standing away from the buds (and if you're using a magnifying glass to look) it will probably be OK to leave outside...