Answer: Hardy hibiscus will come back year after year. After they experience a killing frost, hardy hibiscus can be trimmed back to about 12" above the ground. The plants will sprout new stems and foliage in the spring. If you want to encourage better branching, pinch them lightly early in the growing season. Flower buds form on the ends of branches. Pinching too late may delay blooms. Otherwise, they shouldn't need pruning unless they grow too large for their space. Once the new shoots have emerged the next season, you can prune out any old stems.
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