Question
Hi Jim:  I live southern Ontario Canada.  The two different sized phalaenopsis I bought two yrs ago basicall grow well, and it bloomed twice a yrs the first yr.  The problem I have now is that two three weeks ago I watered them a little too much after their after-blooming rest perio.  the roots look a bit more too wet with a bit of white mould can be seen.  Would you please help me on how to care for them at this point.  I truly appreciate it.  -Jessie Lei

Answer
Hi Jessie Lei,

To begin, an occasional overwatering should not cause too much harm to your phalaenopsis orchids but continual overwatering can be fatal.  After overwatering them it would be adviseable to allow the potting media to become barely moist (almost dry) before watering again, in fact this is how you should water always - waiting until it is barely moist.  I like to lift the pot to determine how wet/dry the pot is, if it still feels heavy I wait but if it feels light I water.  Also, it is best to water them in the morning, this will allow enough time for any water droplets on the leafs to evaporate before nightfall.  

Since you live in Ontario Canada, I take it you grow them indoors all year round.  Phals prefer bright indirect sunlight and there in Ontario with reduced sunlight temperatures, you probably can place them where they will receive direct morning sun until almost noon.  Temperatures should be between 17 C to 32 C for most of the year with a 2-3 week period of night temperatures near 14 C in early fall to help promote blooming.  

Is that really a white mold you see?  Phals are notorious for attracting mealybugs which have a whitish fuzzy coating over them.  Try dipping a Q-tip or cotton swab in isopropyl alcohol and touch the white mold, if the white disappears and you see a tiny insect left, then they are mealybugs and need to be eradicated.  Mealybugs will suck the life out of your phals - a slow death.  The best way to get rid of them is to repot them and thoroughly clean the phals (especially on the underside of leaves) of all mealies.  Be on the lookout for them in the future, miss one mealy and you will soon have more.  

Hope this helps.  Good luck and good growing.

Jim Kawasaki
San Jose, Ca. U.S.A.