Answer: There are many perennials you could use such as: purple coneflower (Echinacea purpurea), black eyed Susan (Rudbeckia), Brazilian verbena (Verbena bonariensis), daylily (Hemerocallis), catmint (Nepeta), lavender, mondarda, phlox, goldenrod, ironweed (Vernonia), asters, and sedums which are all attractive to butterflies. Hummingbirds will also like tubluar flowers such as Aquilegia, Ajuga and Hosta, and vines with trumpet shaped blooms such as the native honesuckle.
Unfortunately I have no way to check what your local HOme Depot would have in stock on hand, but keep in mind the selection does tend to change over the course of the season. Perhaps you can call ahead occasionally and see what they have to save yourself a trip.
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