I was going to ask this question in my bonsai group, but here I will ask it
from a purely botanical point of view. I have a rock planting of three
Kingsville boxwood and one Bahama berry. Because of the Bahama berry, it is
never exposed to frost & spends the winter under lights. The roots of the trees
go down under moss to the bottom of the rock. It is kept on a tray of wet
gravel. In effect, it is a sort of hydroponic arrangement, except for the moss.
I exhibit it as an island in a large water tray. The rock planting is about a
foot tall. What effect would it have on the trees if I set the rock permanently
in a shallow bonsai tray of bonsai soil (which is very gravelly stuff).
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)