Minimum tolerated air temperature on plants if roots are kept warm enough?

[Cleargreen]

Not sure the tree analogy works here since such trees go dormant in winter which is something else altogether.

Keeping the root zone a stable temperature in my configuration is easier then you think, I'll get some pictures up tomorrow to clarify this.
Not sure how I could be offended by your input, I really appreciate it

[Cleargreen]

Bottles sticking out quite a bit but I might change that.



Driver and heatsink from the Invisible Sun can obviously come out as well, not sure yet where the driver for Hans will be placed as it's considerably larger than the IS driver.
Maybe in the rootzone area as well?

[Cleargreen]

I went with a 15 liter SIP bucket instead of the 4x1,5 liter glass bottles for this next round.



A thin corrugated plastic sign to separate the root zone from the plant area. Still have to move that heating mat sensor to go in via the freezer door on the bottom and might tape that front edge down as well.
Not sure the heating mat will even kick on but we'll have to wait till the clock goes on 20/4 as soon as the seed has emerged.