My guess would be it's in way too small a pot right now, Dawg. You could pot it up, use some good, moisture-retentive potting soil, and park it in that spot to see if it survives ok, then plant it permanently if it does. That baby has never been anywhere but in a greenhouse, I'd bet. So it's missing its humid air, too. Spray it with the hose whenever you walk by! Spray the fence, and the walls of the house, too. It will all help raise the humidity.
If they're anything like orchids - and I think they are - they make darker green leaves in the shade, and lighter green ones in higher light situation. So those dark leaves it has now may get sunburnt and go the way of the dodo. But it will make new leaves with less chlorophyll in them, that will take more sun. Give it a chance and it may adapt quite well.
My P. selloums are big and well established like Lin's rental ones. They get lots of water sporadically in the hot months, regular irrigation at least 3 times per week in spring and fall, (when the humidity can be fairly low, but nothing like So. Cal) and I don't water them at all in the winter. I've never given them any fertilizer. They are under a gigantic live oak tree, and have their roots dug deeply into the oak tree humus. I blow all the oak leaves into the border so each year they get a thick new mulch of oak leaves, and the other 'stuff' that the oak trees drop on them seems to be all they need.
