Recovering a late re-potted tree.

[The Warm Canuck]

I re-potted this Maple in partial leaf and I believe it was showing signs of distress.

I've taken it out of the sun and tried to make a makeshift humidity tent. I've ensured that the tree doesn't touch the sides of the plastic and I've been spraying it a few times a day. Should I be doing this? How much humidity should be maintained in the tent? Should I have condensation in the tent, or just leave the tree to do it's thing?

 

[RKatzin]

To me that's a bit of an overkill. It's early in the season and I have repotted maples at this stage many times. I usually just set them back in the shade for a few days until I see the tree responding positively. Then move it out to a few hours of morning sun for a few days and if it's responding well, back into position on the benchs.
Most of my trees are not leafing out yet, but I picked up a couple of maples from the valley and they had just popped leaf. I went ahead with the repotting, actually potting them as they were dug out of the ground, very loose loamy garden soil. I shook out as much of that as I could, trimmed a few ropey roots and planted all in pumice. That was Saturday and they're all looking good this morning, still holding leaves.

 

[rockm]

This tree doesn't need to be bagged. Too much humidity is abad thing for a stressed out tree. Such an environment encourages fungal and bacterial growth in a weakened tree. Better solution would be to place the tree out of the sun in an area that is sheltered from wind and let it alone for a couple of weeks. ,

FWIW, over the last couple of weeks, I've seen a few posts about using the plastic tent method for recovery and forcing new growth. It's being used because someone saw it in a video on the Net. FWIW ,tenting can have its uses, but it can also be an unnecessary and possibly harmful crutch. In some posts, folks are getting roots emerging well up the trunk--which is because one of the unwanted side effects of putting a plant in a hot humid bag in the dark is to replicate underground rooting conditions--

 

[The Warm Canuck]

Roger that, thank you. When is a tent actually necessary?

 

[rockm]

Roger that, thank you. When is a tent actually necessary?

I've used it only for collected trees that are sluggish to recover. It can work, but it's a last-ditch thing at least for me. Foliage that does emerge under those conditions is extremely leggy and vulnerable to die off in "real life" as in open air and sunlight. You can't unbag it and forget it. You have to gradually introduce the foliage to outdoor conditions over a week or so. It is hardly the miracle cure some think it is.

You will likely get people posting swearing by it now.

 

[WNC Bonsai]

Tenting is used a lot in England where it has been popularized by Tony Tickle and Harry Harrington who both use it on hawthorns. They typically bag newly collected trees in black garbage bags and keep them in there with regular misting. For your tree it would be more common to just pop it into a greenhouse after repotting. I have used a method similar to yours for rooting cuttings but it can be good or bad. One year I had 100% success with my elms cuttings. Then the next year all my sekka hinoki cuttings got moldy and eventually died.

 

[The Warm Canuck]

Tenting is used a lot in England where it has been popularized by Tony Tickle and Harry Harrington who both use it on hawthorns. They typically bag newly collected trees in black garbage bags and keep them in there with regular misting. For your tree it would be more common to just pop it into a greenhouse after repotting. I have used a method similar to yours for rooting cuttings but it can be good or bad. One year I had 100% success with my elms cuttings. Then the next year all my sekka hinoki cuttings got moldy and eventually died.

Isn't what doing not having the same effect as a greenhouse?

 

[Brian Van Fleet]

Roger that, thank you. When is a tent actually necessary?

When you’re camping.

 

[pandacular]

When you’re camping.

I prefer a hammock, when should I use that on my trees?

 

[WNC Bonsai]

Isn't what doing not having the same effect as a greenhouse?

A plastic bag is a relatively small volume and little to no air movement and exchange. Greenhouses are much larger volume, typically have a fan to move air around, and exchange with outside air. They still have fairly high humidity but all of the rest helps keep fungal and bacterial disease at bay. So get yourself a plastic bag big enough to hold your car, install a fan somewhere, add a vent and you might be close.

 

[99 Mile Creek]

Keep the foliage and existing roots slightly moist so the evapotranspiration rate stays low. It won't need as much water as it typically would until the roots reform (few weeks?).

Your container for the tree is also shallow and wide. This will mean your tree has more moisture available to it than a taller pot with the same volume of substrate. I'd be worried about too much watering (rule of thumb: soft and brown too much water. Crispy and brown, not enough).

Also, misting is ineffective unless completely sealed within a greenhouse. So, maybe the tenting can work if you have the material to make a sufficient enclosure. If not fully enclosed, it would be futile, it seems.

FWIW, this is all based on the literature I'm currently reading on bonsai and horticulture. I could have my wires crossed somewhere. Good luck!