Check out clematis armanii, also known as evergreen clematis. Besides keeping its leaves all year, it's not heavy like wisteria, a prolific spring bloomer. Wind a few lights along the edge of the trellis for summer nights.

That sounds perfect. Great landscaping all year round and an accent for the existing pergola. Thanks!

Just followed your link to Crash. Get some TSP (look at directions for dilution) and regular clorox bleach (about 1/3 of big bottle), put in a Home Depot 5 gallon bucket with warmish water. Apply to your "green" deck. (My husband's method is "throw at surface".) Wait about 15 minutes, then powerwash (rent one at HD, or borrow one). Green gone. Trust me. I live in the land of moss. We do this every year to all the wood and concrete surfaces outside our house. Once it's clean the first time, let it dry for a couple of days and stain the wood. Makes it easier next year. You might as well do the arbor before you plant your new vine. Cool place.

Thanks! I've never heard of TSP, but I'll definitely check it out. I've already done a round of laundry detergent mixed with bleach and a scrubbing brush until I got a blister on my hand. It already looks better, if you can believe it.
I'm so glad you liked the house! I'm excited to be restoring it.

Great idea to clean the pergola at the same time. Had you had any luck painting or staining wood decks?

More than I want to recall! We have a sizeable wood deck that we've stained 3 times. (Been here awhile!) Given the weather in the Pacific Northwest, not that many people paint exposed decks. I think you would have best results staining with a fairly opaque product with a sealer within the product. (There are very transparent stains, and others with more color. You can see the difference if you look at displays in the store.) Stain penetrates and covers the surface, painting needs a pretty decent start surface to hold up. Just guessing the wood you are dealing with has been out there a few years, so I think stain might work best after cleaning and allowing days to dry. We usually wait a warm, dry week and clean off any dust or debris that might have gotten on it before staining. If some of the wood is really rough, give those areas a bit of sanding before you stain. Have done the same to multiple arbors.

Great, thanks. Do you have any favorite stains for long-wear?

I've had good luck with Home Depot's Behr products. If you go to one with some photos of your deck, they should be able to recommend what might be best in your area for your specific situation. Prep is important, just as in painting. I'm kind of picky about things, so we've done stain every 5 years or so even though to some people it probably still looked just fine!

We like Sikkens stains and check out sweet autumn clematis as a vine.

5 years or so isn't bad at all. I'm being very careful about prep, as I'm on round 3 of bleaching and washing before a light sanding to prep for staining. I appreciate the advice.

Thanks, and that's 2 votes for clematis. Any idea how that does in the Southeast?

Oh, before I recommended that clematis, I checked nurseries in your area. Am not sure, but I think the autumn clematis is not evergreen, but very fragrant when blooming.

You're so thoughtful to check, thanks. I'll definitely get a power washer because my tide/bleach/hose and scrub with a brush wasn't really cutting it. Although when I added more bleach today it really improved on cutting through the mildew. I'm planning on power washing the siding of the art studio and the pergola too. I'm not normally a clean freak, but I like fixing things.

Let me again recommend TSP/bleach combo for the wood. If you've done it that many times, you deserve an easier process! Once you see the difference a PW makes, you may become addicted. Our driveway went from gross to looking brand new. Just put in the earphones and went at it. Done in nothing flat.

Zone 4 to 9
http://landscaping.about.com/od/vineplants1/p/autumn_clematis.htm

Nice, thanks for checking.