Answer: What a shock it must have been to find you'd beheaded your new butterfly bush! Not to worry, though. The roots should be strong enough to send up new shoots. You won't have to do anything other than keep the roots watered (as if the plant still had foliage). Butterfly bushes are often cut down to ground level (or they die down to ground level in cold winter areas) and they always come back each spring. You might want to place a couple of stakes near where the plant is growing to help avoid this kind of accident in the future. I don't think the top will root, but you can certainly try taking cuttings. Take 4-6" long stem tips, strip the bottom leaves and dip the cut end in rooting hormone. Set these cuttings in a pot of moistened potting soil and keep the soil moist. Set it in a protected spot in the garden - somewhere where it will be shaded. With any luck at all your cuttings will root and you'll end up with several new buttefly bushes.
Best wishes with your landscape.
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