Answer: You have a number of options. Here are a few reliable, hardy plants. Remember that even the hardiest plants will need some extra attention their first season, until they get established:
Gaillardia (blanketflower), daylily, achillea (yarrow), coreopsis, purple coneflower, rudbeckia.
A mix of plants with different bloom periods will provide interest throughout the growing season.
Hope this helps!
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