Just bought my Emerald Arborvitae for an intended hedge so I hope I have better luck with it than you have had. The limiting factor with your site is the shade. I like using boxwood as a hedge but sounds like your situation may not be bright enough. Same goes for the so-called "Sky Pencil Holly". I have Fargesia bamboo in semi-shaded area that does quite well (it's a clumping species so it won't run wild). You also might consider "Cephalotaxus harringtonia fastigiata" (it's the upright growing, Japanese Plum Yew) and is fairly shade tolerant, though it can get to be 3-five feet wide and 8 to 10 feet tall (unpruned).

Sorry, greenfreek, I can't say how well it would do in your zone. I have both the green and variegata in my San Jose garden, and they do great here. We do get a lot of days in the 90's and anything above 95 is considered a heat wave here and we get a few days in the triple digits. Mine are in semi-shade with their roots in a cool shady spot. Maybe growing it in more shade in your area would make a difference. wanda

You really have a lot working against you trying to add to this window. The window is large and butted against the soffit. As Milworkman pointed out, shutters probably are out of the question. I think the best solution would be with shrubs, but then saw the "planter" at the wall base and the sidewalk right next to it. They do grow really skinny shrubs, google tall skinny shrubs for your growing zone. It may just be the photo, but it looks like the window is not centered in the wall which is also working against you. This doesn't look great, but gives you an idea. Hid the tree so it would be more visible.

Sammy, I split my time between living in Sand Springs and in Wichita, and I'm amazed at how differently the plants grow in the two places. Hydrangea will need shade from noon on, no way can it survive out in the sun. My roses are all mixed with perennials, and I try not to leave any ground uncovered! A good place for you to shop for cool shrubs is Bustani Plant Farm just outside Stillwater. He carries a variegated Beautyberry that works well in mixed beds. Tiger Eye sumac is really an eye catcher in with yellow or purple roses. I use black elderberries and ninebark quite a bit to set off pastel colored roses. The newer hardy hibiscus have a much longer bloom period, stay shorter, have interesting foliage, and bloom all along the stem, not just at the top. You might check out some of the smaller varieties of viburnum also. I have some that handle the sun very well. The tall snapdragons are easy to grow from seed, and mine come back every year. You should be able to grow nice clumps of cannas without having to lift them in winter. Nepeta (catmint)...newer cultivars such as Kit Kat and Purrsian Blue, are a great replacement for May Night salvia, as they require almost no deadheading to stay in bloom all summer. The red greggii salvia do well here and bloom from May until October. The new Russian Sage is much neater in form. Coreopsis do well in lean rocky soil, as do veronicas, baptisia, penstemon and achillea. Check out some of the newer baptisias! They are wonderful! I include iris, daylilies, lilium and phlox in my beds, and most summers do not irrigate and somehow they all survive. I think planting intensively helps because the roots are shaded. Small trees/or skinny shrubs that also work well are amalanchier (serviceberry) and aronia. Vitex blooms for a long time, starting well before the crape myrtles. Weigela handle the heat and sun, except for variegated varieties. They do require a bit more water than the other plants I've named. I keep the abelias and beauty bushes in the shade, and even so, they grow very large. Rose of sharon also gets too big for flower beds. I use a lot of ornamental grasses, but I'm careful to find ones that won't seed about. Rudbeckia, heliopsis, gaillardia, echinacea all work for the first year or two, but if you have enriched soil, you may end up with seedlings everywhere and big floppy plants. I allow larkspur and zinnias to drop seed and welcome them back every year. Asclepias, butterfly weed, is a terrific native perennial in our area. Torch lily, kniphofia, is also a heat lover. Right now, the beds are bursting with naked lily (lycoris) blooms. There's lots more that can take our heat and sun...that's all I can think of without walking outside to jog my memory!