Sapphire Surf Caryopteris is one of my favorite plants for butterfly gardens. Wait until late spring to prune. In your zone, you might find there is some winter kill. Once it starts leafing out, you will know what to trim off. As for overwintering, I have just the right video for you! Prepping for Winter has great tips. Since you are on the edge of the zone for caryopteris, you will want to bundle it up for winter.
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