07-27-2012, 08:55 AM
Keep in mind that there is a limit to how long the plant should stay in any medium.
In organic ones, they decompose, so we replace them and throw away the old stuff.
With inorganic media, because they don't decompose, we are "lulled" into thinking it's permanent, forgetting the buildup of minerals and wastes.
If your environment keeps the medium constantly moist, and you flush thoroughly at every watering, the rate of buildup will be minimal. I'm great with the second aspect, "pretty good" with the first, and have plants in the same medium for as long as 8 or 9 years, although they are about to be divided and repotted into fresh stuff.
Precipitation of the minerals occurs as the water evaporates, so the more that happens, the more frequently the medium will need replacement.
Using science and logic
to advance orchid growing