Putting trees in cold greenhouse possibly soon...a few questions

[Cadillactaste]

I have a landscape tree that came with powdery mildew. (Plan on turning into a bonsai next spring) I want to make sure to treat it prior to putting it away...but, it hasn't dropped all it's leaves. Should I then bring it in anyways...or defoliate what is left. Or wait until all the leaves drop?

 

[Nybonsai12]

you start too many threads about this cold greenhouse of yours.....lol

 

[Cadillactaste]

you start too many threads about this cold greenhouse of yours.....lol

True...lol but this is about how to handle one that had that powdery mildew. I read it's important to spray fungicide before wintering if you had it on a tree. But, having leaves still on...how do I go about wintering said tree...into a cold greenhouse. Which is a room that is enclosed with other trees.

Guess I should have titled...powdery mildew and winterization. My gerbil is sleeping so my wheel is not spinning/thinking...but, my main concern is wintering this tree...that I have kept from my other plants so far. In an enclosed building. How would one treat this?

 

[Nybonsai12]

If it is a landscape tree, why not just leave it outside for the winter? I assume it would survive fine, no? and I wouldn't want to expose other healthy plants to a potential problem. I'd treat it and leave it outside. If it had to come in, I'd treat it now in leaf and then bring it in when necessary.

 

[Cadillactaste]

If it is a landscape tree, why not just leave it outside for the winter? I assume it would survive fine, no? and I wouldn't want to expose other healthy plants to a potential problem. I'd treat it and leave it outside. If it had to come in, I'd treat it now in leaf and then bring it in when necessary.

Well...it's still in a nursery pot. Which goes into their cold storage greenhouse if not sold. So I would assume same scenario for wintering...no?

 

[fourteener]

Remove all the leaves off of every deciduous tree. No use bringing in any diseases. I also spray the trees before they come in. All this moisture and pathogens in a tight dark space is a recipe for trouble. Do everything you can to eliminate trouble. Get a fan to keep the air moving and only water if you need to, which should be pretty minimal when things are dormant.

 

[Cadillactaste]

Remove all the leaves off of every deciduous tree. No use bringing in any diseases. I also spray the trees before they come in. All this moisture and pathogens in a tight dark space is a recipe for trouble. Do everything you can to eliminate trouble. Get a fan to keep the air moving and only water if you need to, which should be pretty minimal when things are dormant.

Thanks! So trim them like one defoliates a tree leaving a bit of stem? (Sorry for my ignorance) Is using Liquid Copper Fungicide good stuff to use...or do I need something else? I have a fan in there already.

 

[Dav4]

What species of tree are we talking about here? Landscape nurseries generally don't overwinter their cold hardy stock in greenhouses, but instead leave them outside grouped together with other trees, and have mulch placed around their root zones. As NY pointed out, it's probably overkill to overwinter a landscape tree in your cold house...leave that for the bonsai and the less cold hardy stock.

 

[Cadillactaste]

What species of tree are we talking about here? Landscape nurseries generally don't overwinter their cold hardy stock in greenhouses, but instead leave them outside grouped together with other trees, and have mulch placed around their root zones. As NY pointed out, it's probably overkill to overwinter a landscape tree in your cold house...leave that for the bonsai and the less cold hardy stock.

It's their U shaped building...no heat...just protection from wind. It's a lilac...potted. So maybe calling it a greenhouse was wrong wording.

I can do that...I do have an area I could toss leaves up around...for the ones in nursery pots. Less work for me in general...and no fear of powdery mildew. Two lilacs...and one Hemlock. The hemlock took and had suffered from last winter being outdoors...it's why I got it for free. Some loss to die back from winter cold. Which scares me leaving it outdoors...I guess.

 

[Dav4]

Syringa vulgaris, the Common Lilac, is extremely cold hardy, at least down to zone 3. I'd find a place in your yard out of the wind and sun, mulch the pot in, and forget about it until spring.

By the way, Hemlocks, being evergreen, are much more susceptible to the effects of winter sun and wind, then deciduous trees. They are quite cold hardy, too, but need more protection then a lilac would.

 

[davetree]

Thanks! So trim them like one defoliates a tree leaving a bit of stem? (Sorry for my ignorance) Is using Liquid Copper Fungicide good stuff to use...or do I need something else? I have a fan in there already.

Liquid copper is an excellent choice to control powdery mildew.

 

[Cadillactaste]

Liquid copper is an excellent choice to control powdery mildew.

Thanks! Good to know.

 

[Cadillactaste]

Syringa vulgaris, the Common Lilac, is extremely cold hardy, at least down to zone 3. I'd find a place in your yard out of the wind and sun, mulch the pot in, and forget about it until spring.

By the way, Hemlocks, being evergreen, are much more susceptible to the effects of winter sun and wind, then deciduous trees. They are quite cold hardy, too, but need more protection then a lilac would.

Alrighty then...I will winter them outdoors...maybe up against the house under the back stairs to the kitchen? It would get some wind protection...yet, still get snow and such.

 

[Dav4]

Alrighty then...I will winter them outdoors...maybe up against the house under the back stairs to the kitchen? It would get some wind protection...yet, still get snow and such.

Sounds good...you want it to freeze solid, out of the wind and sun, and stay that way until spring.

 

[MidMichBonsai]

Alrighty then...I will winter them outdoors...maybe up against the house under the back stairs to the kitchen? It would get some wind protection...yet, still get snow and such.

That's what I would do. I live in 5b as well and just stack all of my trees up against the north side of the house packed tightly together and then use pine needles to mulch the base of the pots. I then surround them all with burlap and patiently (or perhaps not so patiently) wait until Spring.

I did this last winter and even though it was very severe, I did not lose a single tree.

Best!

 

[fourteener]

If your overwintering a landscape tree along with all of your other bonsai trees, I would simply do the same thing for them as you do for all the rest. Landscape trees still need some form of protection in a northern winter. Air temperature is colder than ground temperature, thus you can't just "leave it out". I group all my trees and wanna-bes in the same place. Pot-to-pot, mulched over with a fence for critters and some feed for those critters that would want to girdle your tree. A layer of snow over the top completes the deal. In your case having it in your gazebo, keeps out the elements to some degree.

 

[Cadillactaste]

If your overwintering a landscape tree along with all of your other bonsai trees, I would simply do the same thing for them as you do for all the rest. Landscape trees still need some form of protection in a northern winter. Air temperature is colder than ground temperature, thus you can't just "leave it out". I group all my trees and wanna-bes in the same place. Pot-to-pot, mulched over with a fence for critters and some feed for those critters that would want to girdle your tree. A layer of snow over the top completes the deal. In your case having it in your gazebo, keeps out the elements to some degree.

This was why I had planned on putting them in the cold greenhouse. Its there...and prepared for dormant trees. Wired into a thermostat set at 30F. Is a baseboard heater.