Thanks Silken and Jeanette! Silken to answer your question, I have two oscillating fans that provide a gentle air movement during the day - they run on timers from about 8 AM to 6 PM. The GH is open to the house all the time as it is the access to the garage.
Sounds like a mat or other heating open such as heat tape is in my immediate future
. I like the Mylar idea for light and heat reflection too. I was thinking of using the mat on a small shelf I have (11 x 30 in) and a second mat for the Phals in the lower light district.
In the winder months, I rely on sunshine for light and it seems to be adequate.
Once I move everyting indoors, I will post photos. I am currently waiting for the GH repariman to reaplce a couple of windows that lost that double pane seal and are growing disgusting stuff between the panes of glass. We put the GH in about 15 years ago, so I'm not concerned about the glass replacement - it's due.