Help finding the right plant for a very challenging spot in my yard :-(

Posted by lee Stanfield ^Ž , Aug 28,2007,19:53

I have a planting area surrounded on 3 sides by covered patios with waist-high pony walls on the North and East sides and a knee-high pony wall on the South side (see diagram below). The distance between the North and South roofs is about 5 ft. so the planter is about 5 ft. by 8 ft.
The planter is on the North side of the house, here in Tucson, Az., so it receives no direct sunlight except mid-day in summer only (which, of course, here in the desert, is the worst time to have exposure to the direct sun). So, I have stretched shade cloth from the roof on the North side to the roof on the South over the planter so that even in the summer it will receive shaded sunlight (because I assume that any plant which can tolerate direct Tucson mid-day summer sun could not endure the other 8 months or so of no direct sunlight when the sun is farther to the South and so is blocked by the house and roof). So this means that this area is in shade all the time, and receives only indirect light. However, I would not call it deep shade, since it does get a lot of pretty bright indirect light.

/\
l North
l

I covered area
I_________________
I ^
Planter I (5 ft.) covered area
_________________I v ---->
I < (8 ft.) > East
l
covered area

l
l South
\/

Anyway, I would like a shrub-sized plant with large or medium-sized colorful flowers for this planter. It needs to be shrub sized to show up over the pony walls, and I really want something with bright color because it is in a perfect spot to be seen from the house and patios, etc....(you know..... like a show piece)
Right now I have a Camelia there, which would be perfect, except someone forgot to tell that to the Camelia. It is not thriving nor has it bloomed at all since I planted it about a year and a half ago. When I planted it, I removed all of the soil around it in the planter for about a 2-ft. radius from the plant, and replaced it with a mix of composted forest mulch, and have been doing my best to keep the soil acidic. However, now I am being told by others that I am fighting a losing battle, and that Camelias just never do well here, and that I will never get the soil and water the right PH for it, & will never be able to get it to look good. Right now it is mostly bare branches with scatterings of some leaves (mostly on the ends of these long mostly-bare branches). It hasn't put out any new growth since this spring (at least this year it is not all brown like it turned last year) but even though I have been watering it with our harvested rainwater every other day and it is watered by our drip irrigation on the days in between, it still is just barely holding on.... and looks like anything but a showpiece!
Is there a plant that will do what I want in this spot, or should I just give up and paint a mural on the pony wall ?