Why plant perrenials?

You can plant many broad leaf evergreens, include cold-hardy palms to make a year round oasis.

I'd love to plant some evergreens. Any specific suggestions? I've considered planting some palms but I've heard that some are "dirty" around the pool. I'm not sure which species to choose. I'm open for ideas that work in our climate. Thanks!

Are you specifically talking about plantings behind the hot tub?

Yes, the area behind the spa as well as the area between the pool deck and the house (not pictured). I also have some hydrangeas planted between the deck and the retaining wall but I'm not sure how well they will do because they may get too much sun.