I think a purple queen would do OK there. You can prune it to keep shape also, even though it usually doesn't get too big at about 1-2 feet in width.

Some dwarf canna lillies may also be nice.

Purple coneflower (echinacea purpurea) and black-eyed Susan (rudbeckia fulgida) are long blooming perennials that should both do fine with five hours of sun; we have 'Magnus', 'Goldsturm', and another coneflower cultivar I can't recall growing in similar conditions. Mexican hat (ratibida columnifera) is even longer blooming and planted on the east side of a fence where it gets only morning sun - though can require a ring-style support where there is nothing around it to lean against.

Golden columbine (aquilegia chrysantha) is another nice option that may work if some of your space has dappled shade. Ours can handle five hours of sun in the spring, but is partially shaded by crape myrtles during the summer heat.

'Purple knockout' lyre-leaf sage (salvia lyrata) should also work and provides some nice foliage color beyond its bloom time.

The aromatic asters (symphyotrichum oblongifolium) we have in these partial shade locations flowered well, but tend to stay pretty low.

Here is a link that might be useful: Salvia lyrata 'Purple Knockout'

This post was edited by bostedo on Fri, Mar 21, 14 at 12:18

Whitecap, try ruellia squarrosa. Similar bloom to your dwarf ruellia, but completely different foliage and shape. Should do well in that location. If you are in the San Antonio area they have them now at Rainbow Gardens. Also, if you are local, I'd like to invite you to our plant swap coming up April 5. If you'd like more info please email me directly. (patty)

I have a similar bed and have had good luck with skullcap (red) and heart leaf skullcap should do well there. I also have firecracker plant (St. Elmo's fire) in that bed and has done very well. Lots of iris and ruby crystal grass with good luck too.

Thanks all. I had to look some of this stuff up to learn I've already had some experience with it. Symphyotrichum oblongifolium = fall aster, which I just set out. Purple queen = Tradescantia, great for subdued color contrast. I'm using it in several places. Ruellia squarrosa = Blue Shade. I've got a side yard of it, and just posted a note about it on the "What to plant under live oak" thread. I'm looking for showy blooms that will be visible from a distance, which takes out skullcap. I tried it once, and it thrived, but developed a big center "bald spot" in late summer. No plant more elegant than the columbine, early on, but mine became awfully ragged, in late summer. How could I forget the firecracker plant? It was gorgeous. Only thing, it sent out those broomstraw type fronds for 3 or 4 feet in all directions, and the tips started rooting. It was just too rambunctious. I think I'm going to try a white coneflower. I once tried a yellow one, but didn't care for the color. Don't know why it didn't occur to me earlier, but the white plumbago would give me some variety. Also picked up a Coreopsis, with crossed fingers. Castro, I'll keep April 5 in mind.

These might work: (some are deciduous shrubs)
Jerusalem sage
Black and blue salvia
Salvia coccinea
Clethra ruby spice
Virginia sweetspires
Turk's cap

Whitecap, you may know this already, but maybe someone else can use the information; you can cut that ratty looking columbine folliage all the way to the ground in summer and it will immediately produce beautiful new fresh leaves.

Hope you come to the plant swap April 5. More info on the exchanges page.

Thanks, again. Some of these look interesting, and I'll keep them in mind as potential replacements. I did try the black and blue once, with mixed results. It shot up rapidly, and became somewhat unstable, so I had to stake it. I've never seen such a hummingbird magnet, though. I had to part with it when I discovered it was sending out little black and blues 3 and 4 feet away, by underground roots.

Never occurred to me to cut back columbine. Good to know.