Bark is notorious for drying out very fast when fresh or until
bacterial/fungal action begins to break it down just a bit. Then it can hold
more water. For that reason, many people will add some sponge rock and maybe
a bit of peat or coir (depending on the orchid to be potted) to help hold
some moisture in a new potting. In most cases, the peat or coir will have
washed through when the bark begins to really do its job depending on how
much you added. Watering a fresh pot in with Physan will also help in that
it is 1) a surfactant making water wetter, and 2) a microbiocide which
should help with any of those unavoidable cuts and bruises made during
repotting. I've never liked potting phals in bark (I know there are plenty
of heavy waterers who do and do well with it). On the opposite extreme, I've
seen phals in spaghnum and Fafard #3 potting mix (a peat base mix). To each
his own according to watering habits. Like a number of others on this list,
I have several thousand plants and it would be impossible to water them
differentially according to what they would like. So you must adapt the mix
to your watering habits to hold enough water for the plant until your next
round. Unfortunately, this takes practice and time and maybe a dead plant or
2 (or 3,...). Everyone on this list, if being truthful, would admit to
killing plants from over or under watering at least until they mastered
their mix. Then you kill fewer.
Gary
"boothbay" wrote in message
...
I recently repotted my Phal and Dend with just fir bark and charcoal
mixture. In fact was bought in home depot marked for orchids. Water it then
about a couple of days ago and today, I noticed one leaf turning pale on
the Phal and on the Dend the 3 remaining flowers were sort of curling to
itself. Not a good site. I took them both out and sure enough except for
the very bottom of these clay 4" inch pots were dry. Some of the roots were
rotting and I clipped the bad ones off. But they were healthy looking a
couple of days ago. Did the repotting do this? Are they that sensitive? I
like it when the botanical garden book that I have on orchids recommends to
water them at best weekly with a fir bark soil arrangement. Mine needed it
in 2 to 3 days. Its enough to drive one insane...only kidding.