Winterizing my bonsai

[Ovaldes2019]

Hi all,

Looking for some help. I’m located in Martha’s Vineyard New England zone 7A. In past years I stored my bonsai in the unheated garage over the winter. This year I was thinking of storing my bonsai outside next to a corner of my house and mulch them all in and burlap. What is your guys honest opinion? Outside my pines, junipers and cedars will get sun and plenty of water over the winter. If I store them inside they will get no sun but less fluctuation of temperatures.

 

[Lorax7]

If you can put them along the north side of a structure, that’s better than at a corner. The idea is that they are kept in partial shade all winter, so they stay frozen once they freeze and avoid waking up prematurely in the spring when we have a few warm days following by a return to freezing temperatures.

 

[Ovaldes2019]

If you can put them along the north side of a structure, that’s better than at a corner. The idea is that they are kept in partial shade all winter, so they stay frozen once they freeze and avoid waking up prematurely in the spring when we have a few warm days following by a return to freezing temperatures.

Do cedars need light when dormant? I know some say yes some say no.

 

[Lorax7]

Do cedars need light when dormant? I know some say yes some say no.

I don’t think any temperate forest species needs light while dormant. Can evergreens benefit from having some light during winter? Probably. Should providing light be prioritized over ensuring thermal stability? Absolutely not.

 

[MSU JBoots]

I’ve always stored mine outside mulched in with a wind screen. I’ve only lost one tree that way and it was a very weak cork bark JBP grafted seedling that probably shouldn’t have been left outside. Granted I’ve only been through 3 winters with my bonsai but it seems to work fine.

 

[WNC Bonsai]

I’m in zone 7a too and I put mine on the north side of my porch and mulch with pine needles. I have a few that are super hardy and those I usually just place on the ground in a protected area under some pines. One thing to do is toss a liberal amount of Molemax to prevent mice and voles from gnawing on your trees. Been using it for years and so far no damage.

 

[MSU JBoots]

I’m in zone 7a too and I put mine on the north side of my porch and mulch with pine needles. I have a few that are super hardy and those I usually just place on the ground in a protected area under some pines. One thing to do is toss a liberal amount of Molemax to prevent mice and voles from gnawing on your trees. Been using it for years and so far no damage.

That last one is a good tip. I’ve not had any issue with moles yet but I have them in my yard so I could see it happening. One tip I picked up from someone was to wait for a hard freeze or two so the critters have already found a different home for winter. Seems to work but my sample size is small.

Question for you though. You said your most hardy trees sit on the ground. With your others do you heel them into the ground or just set them on the ground then surround them with mulch? I do the former but have been considering the later for next year.

 

[czaczaja]

Mulch, protect from cold drafts and protect from rodents. Maybe consider a cold frame but they should be fine outside. Does the temp fluctuate significantly in your area?

 

[WNC Bonsai]

That last one is a good tip. I’ve not had any issue with moles yet but I have them in my yard so I could see it happening. One tip I picked up from someone was to wait for a hard freeze or two so the critters have already found a different home for winter. Seems to work but my sample size is small.

Question for you though. You said your most hardy trees sit on the ground. With your others do you heel them into the ground or just set them on the ground then surround them with mulch? I do the formert my but have been considering the later for next year.

With the really hardy ones such as larch, blue spruce, Austrian pine I just gather them together under a clump of pines which serve as a wind break and don’t bother to mulch them. Less hardy stuff like trident maples, JBP, elms get the mulch treatment. I put my small stuff like Sekka hinoki, rooted cuttings, seedlings and a cork oak in a window well about 3’ under ground which serves as a cold frame that I can access from inside my garage. If you have moles then you likely also have voles as they tend to use the mole runs also. Apparently just about all rodents hate castor oil which is the main ingredient in Molemax. Its just baked clay saturated with the stuff so is safe to use around pets and other critters. The only time I have gnawing problems is after I put trees back put on the stands and the squirrels will occasionally target one.

 

[RJG2]

With the really hardy ones such as larch, blue spruce, Austrian pine I just gather them together under a clump of pines which serve as a wind break and don’t bother to mulch them. Less hardy stuff like trident maples, JBP, elms get the mulch treatment. I put my small stuff like Sekka hinoki, rooted cuttings, seedlings and a cork oak in a window well about 3’ under ground which serves as a cold frame that I can access from inside my garage. If you have moles then you likely also have voles as they tend to use the mole runs also. Apparently just about all rodents hate castor oil which is the main ingredient in Molemax. Its just baked clay saturated with the stuff so is safe to use around pets and other critters. The only time I have gnawing problems is after I put trees back put on the stands and the squirrels will occasionally target one.

I bought a gallon bottle of pure castor oil to use.

When you use mole max, do you just sprinkle it around everything?

I just sprayed all around where I'll be storing mine for the winter, and will spray a couple more times.

Maybe I'll soak some diatomaceous earth to sprinkle as well. I could also spray the mulch I'll use, but I'm guessing I don't want oil runoff going into my pots...

 

[WNC Bonsai]

I bought a gallon bottle of pure castor oil to use.

When you use mole max, do you just sprinkle it around everything?

I just sprayed all around where I'll be storing mine for the winter, and will spray a couple more times.

Maybe I'll soak some diatomaceous earth to sprinkle as well. I could also spray the mulch I'll use, but I'm guessing I don't want oil runoff going into my pots...

Yes, you just sprinkle the granules among and over the pots. I have never tried using pure castor oil, I don’t even use dormant oil on my trees, somI don’t know if it would present any problems as a spray. The idea of soaking it into diatomaceous earth probably would work.

 

[WNC Bonsai]

Mulch, protect from cold drafts and protect from rodents. Maybe consider a cold frame but they should be fine outside. Does the temp fluctuate significantly in your area?

The temps have become very variable here the last decade. We now regularly get several mid-winter warm spells that are playing havoc with fruit trees breaking dormancy and then the flowers freeze so no apples, peaches, etc. Georgia which is known for peaches had to import them from California last year after the freezes wiped out most of their crop. And for the last 2-3 years we have had late spring freezes here after some trees break dormancy which resulted in damage to new growth on bonsai. I plan to buy/build a green house next summer just to be able to protect my trees from those late freezes.

 

[czaczaja]

The temps have become very variable here the last decade. We now regularly get several mid-winter warm spells that are playing havoc with fruit trees breaking dormancy and then the flowers freeze so no apples, peaches, etc. Georgia which is known for peaches had to import them from California last year after the freezes wiped out most of their crop. And for the last 2-3 years we have had late spring freezes here after some trees break dormancy which resulted in damage to new growth on bonsai. I plan to buy/build a green house next summer just to be able to protect my trees from those late freezes.

Yeah I've invested in a nice greenhouse this summer. Weather has really changed from the 'usual' the past couple of years.