Named for Penny McHenry, the founder of the American Hydrangea Society, this vigorous hydrangea is great to zone 5 based on recent surveys. It will even bloom twice if pruned after first blooms. Penny Mac is great for those areas where early fall or late spring frost kills other hydrangea buds. The blooms are HUGE and are pH sensitive. The blooms will age red for added fall color. We miss you, Penny!