I've heard that both of those can handle cold temps and come back from the roots, though I'm not sure about zone 5. I have both but keep them at about 75 F under HID lights. I don't trust that they'll make it over our winter, besides that they'll bloom year round if kept inside. If the temp in your greenhouse is only 50 F during the day than it's probably quite cold at night. The foliage could be dying back due to the low temps. I'm in zone 7a and our greenhouse can get down to freezing if we don't have a heater going Dec-Feb. You might want to cut back the damaged foliage and put them in a warmer location. If they are to over-winter in the greenhouse you will want to limit the amount of water they are getting. You might also want to insulate the pots.

Thanks karyn1. I checked, and the greenhouse is heated to 50 F so that's the lowest the temps will go. Both are still flowering, although not nearly as much as they did a few months ago. I'm pretty sure that the mottling on the leaves and the loss of some leaves is due to the temperatures, 50 is a little on the low side for passionflowers.

I just had a caerulea survive about 5" of snow. Daily temps here have been in the high 30's and it's still alive.

Pretty sure lavender will flop at about 45 tho.

As for the discoloration I would suspect lack of fertilizer or light- Try some miracle grow.

Good luck-