Answer: Assuming they are grown on their own roots (or if grafted, the graft should be planted below the soil) they should be just fine. Mulch heavily in late fall after a few freezes. In early spring cut them back to remove any winter damage or to about a foot high, which ever is more. Gradually remove the excess mulch to leave a layer about three inches deep. Also fertilize and/or topdress with compost in early spring. Even if they die back to the ground they should regrow and bloom next summer.
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