Newbie: Low temps and heat mats
Hello fellow AV lovers. I'm new here and don't have an AV society less than an hour's drive away, so I go online for all my info and I've read the AV book by Stork.
20 years ago I had a handful of AV's and had great success with them in my lab at work in a south facing, DC window. I no longer have those, but in Fall 2011 I started up again with dismal success. I had them in a cool, very bright, East and South room, top watered (carefully) every 2-3 days (they were in small pots) but never kept them soggy. All 6 succumbed to powdery mildew and some kind of rot. After the PM, as a leaf grew large and it's stem started touching the rim of the pot, it would start to rot from there and go limp. I learned about lysol, Physan etc. etc.
This fall I ordered another 6 from Lyndon Lyon and they are doing great, but I am concerned that my winter room temps stressed my old ones to the point of getting PM. I moved them to the living room in a North window. Daytime temps are 69 and 62 at night. I just bought a heat mat and temp controller to keep them warmer. I can't find advice on what temp to set it at. Also, since more water will be evaporating from their pots, should I put them on a plastic grid over a half inch of water or will all that humidity make them too moist?
Thanks for your advice!