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Author Topic: Root heating?  (Read 932 times)


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Root heating?
« on: December 29, 2017, 07:32:03 AM »
Has anyone ever heard of the use of root heating as a means to zone-shift?  It's something I've been thinking about with the big greenhouse project, whether it might be possible to create an artificial microclimate so that warmer-weather plants (but not ultratropicals) could be grown outside, freeing up more interior space for ultratropicals-only. 

It strikes me from my reading that a large portion of plants are tolerant of having freezes affect their aboveground portions (at least for limited periods of time), but are zone-limited by their inability to withstand their roots freezing (and staying frozen all winter).  Likewise, when it comes to "growing seasons", it seems that it's often soil temperature that's one of the leading, if not primary, constraints on when and how fast plants grow.

Well, here in Iceland we have hot geothermal water, cheap.  It should be pretty easy to keep all but the topmost layers of soil from freezing without requiring an excessive amount of hot water (particularly if the top layers are blended with something like scoria to be extra insulative).  Likewise, we could easily boost "growing season" root temperatures by 10C or so.  It seems to me that such an artificial microclimate (particularly when combined with windbreaks) might prove amazingly effective. But I've never heard of anyone trying it before. Have any of you?
« Last Edit: December 29, 2017, 02:50:41 PM by KarenRei »
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Triloba Tracker

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Re: Root heating?
« Reply #1 on: December 29, 2017, 02:11:35 PM »
My understanding lines up with what you've outlined as well.

I have not tried that, but it seems that logically it might work.

Your post is very coincidental though, as I am overwintering some Asimina triloba potted seedlings in my home crawlspace. Temps dipping to 8 degrees F Monday night. So far the microclimate down there has been above freezing but the coldest we've had so far is about 17. Not sure if 8 will drop things below freezing. So, I too am thinking of ways to heat the root zone. (of course, not long term as you're describing). Anyway, just a coincidence.

Good luck! Will be interested to see what others have to say.


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