Help! Insane amount of mold on all of my trees in coldframe :'(

[Leo in N E Illinois]

I have also been expanding the number of trees that I do nothing to protect. For these if they are growing on the ground, I just leave them where they are growing, for the entire winter. These are trees in plastic grow out containers, pots, nursery cans, Anderson flats, etc. None of these are in fine Tokoname pottery. For trees on benches, they simply get moved to the ground below the bench. I used to throw a tarp over, now I don't bother.

The trees you can do this with will depend on your local climate, and micro-climate. My list of successful trees to do this with is not going to be the same that you can do this with. It works well with species of trees that are native to your area or areas one or more climate zones colder than you live in.

Some successful for zone 5b on the ground relatively exposed wintering.
Amur maple - Acer ginnala, almost all species of Amelanchier, Tsuga canadensis, Picea pungens, Picea engelmanni, Picea glauca, Picea orientalis, Malus crabapple, dawn redwood, Metasequoia and Parthenocissus - Virginia creeper also do well this way.

The larger leaf varieties of Chaenomeles, 'Contorted White' and 'Toyo Nishiki' were successes. Note 'Chojubai', 'Hime' & 'Kan Toyo' did not like this treatment and died.

also successful were Thuja occidentalis, all my Junipers, eastern white pine, Pinus strobus, also Pinus banksiana, Jack pine. And highbush blueberries.

Two notable failures, which I don't understand, as they are hardy in the landscape much further north than I am is Ginkgo and bald cypress. For some reason Ginkgo in an Anderson flat did not survive just set on the ground. Another consistent failure is Bald Cypress. Again, in the landscape is fully hardy, but in a pot fails for me.

Note, any tree in a fine ceramic pot gets protected, mainly to protect the pot. I have had too many pot that were supposed to be freeze-thaw resistant break on me. So I just protect all the good pots, whether the tree in the pot needs it or not.

 

[rockm]

This is my fear. Since all of the rain we have been getting has not fallen on my trees, I am hoping that I did not overwater. I don't think that I've been vigilant enough about unburying and then checking each pot

I also keep a lot of my trees in mulch beds on the ground in the backyard. As I put the trees into storage in the fall, I water them well, put them on the bricks on the solid patio surface, THEN cover with eight or nine inches of mulch that I also water well. The bricks allow space underneath the pot, underneath the mulch to drain. I don't need to water ANY of them, provided it rains or snows on the pile every couple of weeks. If the soil in the pot drains, it will drain underneath the mulch. Haven't had to worry about watering overwintering trees for a very long time... I don't unbury my trees to make sure they'r e watered. That can be like waking a baby up to see if it's having a nice nap. It's unnecessary. I just make sure the top two inches of mulch has some moisture in it. If so, it will be moist all the way through to the pot and below.

 

[TheEmpireNeverEnded]

I have also been expanding the number of trees that I do nothing to protect. For these if they are growing on the ground, I just leave them where they are growing, for the entire winter. These are trees in plastic grow out containers, pots, nursery cans, Anderson flats, etc. None of these are in fine Tokoname pottery. For trees on benches, they simply get moved to the ground below the bench. I used to throw a tarp over, now I don't bother.

The trees you can do this with will depend on your local climate, and micro-climate. My list of successful trees to do this with is not going to be the same that you can do this with. It works well with species of trees that are native to your area or areas one or more climate zones colder than you live in.

Some successful for zone 5b on the ground relatively exposed wintering.
Amur maple - Acer ginnala, almost all species of Amelanchier, Tsuga canadensis, Picea pungens, Picea engelmanni, Picea glauca, Picea orientalis, Malus crabapple, dawn redwood, Metasequoia and Parthenocissus - Virginia creeper also do well this way.

The larger leaf varieties of Chaenomeles, 'Contorted White' and 'Toyo Nishiki' were successes. Note 'Chojubai', 'Hime' & 'Kan Toyo' did not like this treatment and died.

also successful were Thuja occidentalis, all my Junipers, eastern white pine, Pinus strobus, also Pinus banksiana, Jack pine. And highbush blueberries.

Two notable failures, which I don't understand, as they are hardy in the landscape much further north than I am is Ginkgo and bald cypress. For some reason Ginkgo in an Anderson flat did not survive just set on the ground. Another consistent failure is Bald Cypress. Again, in the landscape is fully hardy, but in a pot fails for me.

Note, any tree in a fine ceramic pot gets protected, mainly to protect the pot. I have had too many pot that were supposed to be freeze-thaw resistant break on me. So I just protect all the good pots, whether the tree in the pot needs it or not.

What steps do you take to protect your good pots? Do you take any measures to protect against dessicating winds? And critters, for that matter?

 

[TheEmpireNeverEnded]

I also keep a lot of my trees in mulch beds on the ground in the backyard. As I put the trees into storage in the fall, I water them well, put them on the bricks on the solid patio surface, THEN cover with eight or nine inches of mulch that I also water well. The bricks allow space underneath the pot, underneath the mulch to drain. I don't need to water ANY of them, provided it rains or snows on the pile every couple of weeks. If the soil in the pot drains, it will drain underneath the mulch. Haven't had to worry about watering overwintering trees for a very long time... I don't unbury my trees to make sure they'r e watered. That can be like waking a baby up to see if it's having a nice nap. It's unnecessary. I just make sure the top two inches of mulch has some moisture in it. If so, it will be moist all the way through to the pot and below.

My mistake might be thinking that the potted matrix might be dry despite the mulch being damp

 

[Orion_metalhead]

I also keep a lot of my trees in mulch beds on the ground in the backyard. As I put the trees into storage in the fall, I water them well, put them on the bricks on the solid patio surface, THEN cover with eight or nine inches of mulch that I also water well. The bricks allow space underneath the pot, underneath the mulch to drain. I don't need to water ANY of them, provided it rains or snows on the pile every couple of weeks. If the soil in the pot drains, it will drain underneath the mulch. Haven't had to worry about watering overwintering trees for a very long time... I don't unbury my trees to make sure they'r e watered. That can be like waking a baby up to see if it's having a nice nap. It's unnecessary. I just make sure the top two inches of mulch has some moisture in it. If so, it will be moist all the way through to the pot and below.

What kind of protection against animals and rodents do you have for your plants on ground?

Any pictures of your overwintering setup? I also have not had to water my overwintering trees in a good two months.

 

[Leo in N E Illinois]

What steps do you take to protect your good pots? Do you take any measures to protect against dessicating winds? And critters, for that matter?

My relatively urban back yard has several feral cats, someone's pets left outdoors and bred. They tend to keep mice, voles and rabbits down. I never feed them, they just hang out in my yard for some reason. The local coyote population is fairly high, they keep deer and other critters in check. They also thin the cat colony occasionally. I love survival of the fittest. (as long as it isn't me being culled from the gene pool). So animals are not a big problem. The trees are spread out enough in the yard they don't make a good ''nesting area''. The trees left out are in plastic pots. I have found desiccating winds to not be a problem with the species listed. Notice, I did not list Japanese maple. I do have to protect them.

What do I do with trees in good pots? They go into an underground, unheated well house. This is a 5 x 6 x 4 foot room I can access from my basement, and it juts out of the foundation, the roof of the room is my ground level patio in the back yard. Ceiling is only 4 foot from the floor, so I do have to stoop to get in there. Not a common feature for the average home. It was an early 1920's farm house, without municipal water, that later was retrofitted for city water. It hovers between 32 F to 40 F all winter. Really a nice feature. trees in good pots, trees that are not quite fully winter hardy all go into this well house. I keep JBP and JMaples, and Satsuki azaleas in there. 5 months dark, no problem, because it is dark AND cold. But above freezing.

 

[TheEmpireNeverEnded]

My relatively urban back yard has several feral cats, someone's pets left outdoors and bred. They tend to keep mice, voles and rabbits down. I never feed them, they just hang out in my yard for some reason. The local coyote population is fairly high, they keep deer and other critters in check. They also thin the cat colony occasionally. I love survival of the fittest. (as long as it isn't me being culled from the gene pool). So animals are not a big problem. The trees are spread out enough in the yard they don't make a good ''nesting area''. The trees left out are in plastic pots. I have found desiccating winds to not be a problem with the species listed. Notice, I did not list Japanese maple. I do have to protect them.

What do I do with trees in good pots? They go into an underground, unheated well house. This is a 5 x 6 x 4 foot room I can access from my basement, and it juts out of the foundation, the roof of the room is my ground level patio in the back yard. Ceiling is only 4 foot from the floor, so I do have to stoop to get in there. Not a common feature for the average home. It was an early 1920's farm house, without municipal water, that later was retrofitted for city water. It hovers between 32 F to 40 F all winter. Really a nice feature. trees in good pots, trees that are not quite fully winter hardy all go into this well house. I keep JBP and JMaples, and Satsuki azaleas in there. 5 months dark, no problem, because it is dark AND cold. But above freezing.

I'm envious. I hope to someday live somewhere with such a room that I can utilize.

 

[Japonicus]

I also keep a lot of my trees in mulch beds on the ground in the backyard...

Curious what folks do with their mulch after Winter has passed.
I started a thread on this in general discussion what I'm doing with mine
but not everyone has a big yard to just move their mulch to landscape shrubs/trees/beds...
I sure can't. The garbage men refuse to take any wood or plant material even though
it is biodegradable unlike the plastic we shove down their throats since we don't have a recycle program.

 

[rockm]

Curious what folks do with their mulch after Winter has passed.
I started a thread on this in general discussion what I'm doing with mine
but not everyone has a big yard to just move their mulch to landscape shrubs/trees/beds...
I sure can't. The garbage men refuse to take any wood or plant material even though
it is biodegradable unlike the plastic we shove down their throats since we don't have a recycle program.

My backyard is 25x25 feet or less. I move mulch to our townhouse community beds and around landscape trees near my house. Done it for years, no one complains because it's free mulch.

 

[Orion_metalhead]

Checked on my trees in the shed today.. saw some white mold as well on the cruddy mulch they were planted in. I moved the trees behind the shed under an old metal shelving unit for some protection and air flow. Going to try the hydrogen peroxide trick mentioned above tomorrow. Will let you know how it works!

 

[TheEmpireNeverEnded]

Checked on my trees in the shed today.. saw some white mold as well on the cruddy mulch they were planted in. I moved the trees behind the shed under an old metal shelving unit for some protection and air flow. Going to try the hydrogen peroxide trick mentioned above tomorrow. Will let you know how it works!

Dastardly mold. Please do let us know.

 

[Japonicus]

My backyard is 25x25 feet or less. I move mulch to our townhouse community beds and around landscape trees near my house. Done it for years, no one complains because it's free mulch.

Now ya got my gears turnin'. Thanks. Never thought of asking a neighbor.

 

[Timbo]

While i don't have expensive trees, many of those trees are very hardy up here. The Hornbeam's, Elm's and the Hemlock's are super hardy. I've left mine out on the ground, out of the wind and i haven't lost any. Isn't that a little too much protection for hardy trees in a nursery pot? The Japanese maple is the only one i would worry about TBH.

Also another thought. I'm sure there is a difference of opinion, but through my reading conifers like a little sun, even in the winter and still photosynthesize. At least that is my understanding, I find it hard to prove either way unless grown in glass.

And get a few cats...it will cure your rodent problem!
It will cure your fertilizer problem also!

 

[Tieball]

I find all of this information to be very reassuring. I will have to keep the moldy larger american elm out of the box for the rest of the winter. Where specifically do you put your american elms? Alongside a foundation or structure? On the south side of a building? The north side?

I just have a field area near my home....about the distance people plant a garden away from the house but close enough for a garden hose. It’s on the east side with a clear southern exposure. Nothing special. I was a flat space next to a woods on the east side. It’s fenced to stop deer from grazing. Lower level fencing is common chicken wire fence to keep the rabbits out. Rabbits really like American Elm branches. So I closed the buffet. The rabbit fence runs into the ground to prevent digging access by rabbits. Overall the area is wide open for the most part. I have a sandy soil so drainage is easily accomplished. When it rains it drains...when it snows it just accumulates on top of the trees (most desired care). Whatever nature casts....that’s what the trees get. I do not water at all in the winter...snow and periodic cold rains do the job very well. All the trees do fine even with my winter sub-zero windchills for prolonged days and nights. I don’t know your weather though....only mine.

I have not exactly documented bud swelling or breaking but in my mind I don’t recall ever getting early bud activity. Really late March at the earliest and then into early April. The buds seem to be timed to swell when the ground is warmer and the sun heat accelerates. I do get late spring frosts, sometimes snow/ice but do not recall ever losing buds or leaves. A late spring frost has killed off newly started leaves on the Hackberry trees....and about two weeks later a whole new set of buds burst into new leaves. My trees get all the sun offered....whenever it’s out.

The other trees I mentioned are in the same area. I don’t use colanders or other plastic containers. I have in-the-ground and in-wooden-boxes. I don’t have any trees in bonsai pots.

Because you box shielded your American Elm so far (I don’t know what weather you’ve had or have now though) you might ease it into winter by putting it in a windshielded area. Outside...but shielded. If you have snow start to cover the tree. I’d probably brush off any large areas of mold/mildew before the snow cover.

I think I’ve only lost one tree to winter....that was a smaller Chinese Elm. Not a big loss....I honestly had given upon tree well before winter. I was probably hoping winter would take it away.

 

[Timbo]

Yeah, this year is a lot of freeze/thaw up here, so if anything they get too wet. Normal years we get enough of a January thaw to keep them wet enough. I've lost more trees in a greenhouse, more than likely due to drying out, than i have outside. We also live in line with lake effect snow, we get a decent dumping each year. Only thing that sucks is if we get snow, get a partial melt, it freezes again, it's heavy and can break branches.

 

[bwaynef]

I actually use the concentrated product made for greenhouse use, Zertol, which is at 30% active, strong enough to burn human skin, and I dilute it to 3%. to use to clean leaves, trunks etc. The Zertol product is expensive, so I don't recommend you seek that out.

The product you have is Zerotol (probably Zerotol 2.0). A more consumer-friendly version of this is Biosafe Disease Control (Amazon, non-affiliate link). I haven't used that product as I found it after I bought a container of Zerotol that might out-live myself. It's made by the same company and has the same active ingredients, only in different percentages.

 

[Tieball]

A

Yeah, this year is a lot of freeze/thaw up here, so if anything they get too wet. Normal years we get enough of a January thaw to keep them wet enough. I've lost more trees in a greenhouse, more than likely due to drying out, than i have outside. We also live in line with lake effect snow, we get a decent dumping each year. Only thing that sucks is if we get snow, get a partial melt, it freezes again, it's heavy and can break branches.

Ahhhhhhhh....Lake Effect Snow.....wonderful winter effect.