Browning new leaves on Phragmipedium

[Roberta]

Originally Posted by Dalachin

It was cold last night and I moved the plants off that windowsill and put a thermometer there and it was down to 45. So it is likely that some other night recently it got too cold for that new growth. Guess I need to figure out how to improve insulation in that area… or maybe I should just try growing it warm on the tented shelves.

I think you might have found the problem... many Phrags are not all that cold-tolerant, 45 deg F may be pushing it - and maybe even colder next to the window. (Some Phrags are OK with it, some aren't...Phrag kovachii comes from relatively high elevation and so should be OK with temp, the other parent Phrag besseae definitely prefers warmer. In the case of Phrag besseae, learned the hard way.) So it is probably a marginal situation.