Have a full late morning/afternoon sun area with 4 o'clocks. From about July on, the 4 o'clocks will be big enough to shade the lower plants. There is also a lavender spiderwort in this bed.

Last year I let the yellow sorrel take over, but that takes too much trimming. Would alyssum work? I also have lots of mostly crocuses planted this year, so will need to cover that foliage too.