Help overwintering hinoki sekka

[kodiac]

I'm having trouble deciding how to deal with this tree in the upcoming winter. Typically I take my trees into an unheated garage when the overnight temps get below 20F. This has been fine for my pines and junipers but my garage can hit temps of -10F if the outside temp goes below -20F. I feel like this might be to much to handle for this cultivar. Just wondering if anybody out there has successfully overwintered a sekka in a northerly climate. Any advice would be greatly appreciated...

 

[snowman04]

Nice tree! My winters may go that cold for a nite but my garage stays above 40*. Maybe a small heater with a thermostat local to the plant? I'm sure others have better ideas...

 

[kodiac]

Thanks for the advice. I'm actually thinking about throwing it in the garage beer fridge for a couple of months

 

[snowman04]

Still needs light...

 

[Dav4]

Still needs light...

Not below 35 F, and honestly not a big deal to keep in the dark as long as temps stay below 40 F for most of the dormancy period

As far as overwintering the Sekka, I honestly can't find any info on it's cold hardiness. Understanding that Hinoki cypress, C. obtusa, is very cold hardy and tolerates temps well below 0 F, I'd consider overwintering on the floor of your garage, placed in the warmest spot and mulched with wood chips, assuming your garage is attached. If not attached, it's still likely to be your best spot, shy of digging a cold frame for it. For the record, the soil in the pot is allowed to freeze solid and stay that way all winter... the goal is to protect the root zone from extreme temperature swings, all while keeping the tree consistently cold enough to maintain dormancy until next spring.

 

[penumbra]

I have several. They will be mulched in only but this is cone 6. If I was even a solid cone 5 I would have them in one of my coldframes.

 

[Scorpius]

They don't handle cold weather all that well in my experience. Keep them above 25 degrees fahrenheit.

 

[WNC Bonsai]

I overwintered 10 2 year old cuttings last winter by clustering them and covering the pots with pine needles. They all survived and it got down to 0F back in January. However there was a lot of brown foliage in the spring and it took until July for them to recover and begin putting out some new green foliage. This winter I am thinking of keeping them in a deep window well off my garage which simulates a cold frame. I used it for a cork oak and small Seju elm last winter. In your case I’d consider digging a cold frame and possible adding a heat tape or thermostatically controlled heating pad to keep temps just above freezing.

 

[Deep Sea Diver]

Hinoki “Sekka” are listed as USDA 5 to 8 or even zone 4-8. In the pot at a young age, likely more like a zone 6 tree to be safe.

If the garage is about -10F at the low the tree will definitely be borderline.

One trick folks that winter over trees on their balconies report is to get appropriate sized styrofoam boxes with wood chips to pack the pot in. (Can even put drain holes in the bottom, Just cover them up when it’s cold.) Take the cover off when the temps warm up.

For more on overwintering check out this resource.

https://www.bonsainut.com/resources/overwintering-bonsai-–-theory-planning-and-case-studies-azalea-focus.49/

Cheers
DSD sends

 

[kodiac]

Thanks for the advice everyone. I'm going to try a foam box and monitor the temp inside. I've had a few sekkas in the past and I killed them dead. If I can't keep this one alive I might throw in the towel on these. Again I truly appreciate the feed back. There's only a handful of bonsai enthusiasts in my area and they all are strictly indoor bonsai folks

 

[yashu]

Seedling mats are reasonably inexpensive on Amazon…


1 Pack 21W Seedling Heat Mat for Seed Starting,10" x 20.75" Waterproof Heating Pad for Indoor Plants Germination(M) https://a.co/d/95PtQUB

 

[Japonicus]

How'd it go @kodiac ?