Question
QUESTION: I have 20-30 orchids.  Lately every time I a shoot (right term? stem?) develops it
becomes covered w very small black bugs.  The flowers as they bud and then
bloom are covered with them.  If you run your fingers over them the bugs seem
to be all dead.  What can I do to get rid of these bugs that seem to be coming
from nowhere?  Thank you for your assistance.

ANSWER: Christopher, thank you for your question.  My guess is that you haven't repotted in quite a while.  Thank leads to a decomposed orchid potting mix which is not good for your roots.  The small black bodies you are observing are not bugs but fungal spores.  They aare harmless even if unsightly.  They come from fungi in your potting mix which only occur when the potting mix stays damp.  You need to but a quantity of dry orchid potting mix and begin repotting your plants.  When you unpot a plant, rinse off the roots and remove any that are mushy before repotting.  Be sure you have removed all old potting mix and cleaned the pot thoroughly before repotting.  Repot the phalaenopsis first and any of your plants that show signs of new growth.  Isolate the plants that you repot from the others as you repot. Any plants that do not fall into the above category are resting and should not be repotted until they show new growth.  Since they are resting, cut back drastically on the watering as it can only add to any root problems (water lightly every two weeks).

---------- FOLLOW-UP ----------

QUESTION: Thank you for an excellent answer.  All else being equal, when is the best time
to repot?  I thought it was just after the buds dropped, but your answer seems to
suggest at the time of any new growth (leaves, roots or stem?)
Now I don't use fertilizer, in the past I used 20-20-20 half strength, every
weekly watering, year round.  What would you recommend?

Answer
Christopher, phalaenopsis can be repotted most anytime because they don't have a rest period as found in cattleyas and dendrobiums.  As a rule of thumb, it is best to repot phalaenopsis after flowering.  This is becuase they tend to put quite a bit of energy into flowering and there is more available for growth following flowering. Orchids that have a rest period are best repotted when new growth appears.  I would start feeding when you see new growth.  A balanced fertilizer (eg 20-20-20) is fine. If you use 1/4 tsp per gallon of water at room temperatures you may feed every week.  If you use a greater concentration I would feed every other week and just water in between to flush out excess minerals.