Hehe...good suggestions, Christine. Thanks! In fact, I just planted 'Heavenly Tiara' there, as you suggested. And 'Grand Tiara.' And 'Golden Tiara.' And 'Twilight.' And 'Blue Mouse Ears.' And a fern-leaf bleeding heart.
I decided I didn't want to cool my heels and think about design ideas (I'm notoriously impatient for a gardener), so I went out back and looked around at some of the stuff in my overgrown back bed. I decided to move the Tiaras up to the front yard, so they now line the walkway. (Heavenly and Grand are still tiny, but 'Golden Tiara' is a nice second year plant.) 'Blue Mouse Ears' was a Mother's Day gift from my kids that was still in its nursery pot, so I decided to tuck it into a shady corner near the walk, too. I gave 'Twilight' center position in front of 'Sagae' were it'll hide its "legs," but not detract from the plant. And my dogs have been "excavating" around the bleeding heart, so I rescued it from them.
I'll post a picture of the finished bed as soon as I can take one. It's too dark in that corner now to get a good shot.
