Hey ya’ll, I’ve had a question that I’d love to have a horticultural answer for so ease my mind that kicks against the pricks so hard
One of my main questions is why is it that trees that are recently repotted are more vulnerable to cold damage (roots mostly from what I understand, unless I’m wrong, which I’d love correction if so)?
As someone who runs a plant nursery, I understand that trees that might not normally have cold damage to roots, are susceptible when they’re in black nursery containers above ground. This makes obvious sense as the roots are exposed.
What I’m curious about, is that nursery soil (organic) holds more water and is significantly less porous, which is my understanding as to why I can leave trees (pre-bonsai) on benches in nursery soil, but not bonsai in bonsai soil. If I repot a pre-bonsai to work out the roots and adjust it before it grows out some more, is it just as susceptible if I put it back in nursery soil?
Better put, is the reason for the sensitivity to cold after repotting horticultural, or cultural? Is there a physiological change that removes the cold tolerance, or is it that we remove the moss, and empty the container of any broken down particles that close air spaces within the pot? If it is air spaces, then are Shohin less susceptible after repot as there is less airspace between the soil particles?
For reference if important, I’m in Southern California in an area where our winters are routinely in the low 30’s with occasional mid/high 20’s a few times a month from Nov-Feb, so I’m not talking Colorado cold, which I assume might be a different answer?
I’m also asking as I have plenty of work in the winter and I’m seeking comfort in my early repotting practices to accompany my work . ATM I have the more important recently repotted trees in an unheated garage.