Smooth and panicle hydrangeas are cold hardy; other varieties, not so much. Care for these plants well in winter and they'll ...

Deadhead hydrangeas early; prune timing depends on whether they bloom on new or old wood. Protect plants with mulch, burlap, or cages in cold climates; move potted hydrangeas indoors below 45°F.

Cold damage can affect the spring blooming of hydrangeas, especially bigleaf hydrangeas. Provide some insulation in winter with a cheap, all-natural material.

Most hydrangeas are reasonably hardy, and can tolerate temperatures right down to -10°C. Sometimes even lower, once they’re properly established, but they still require some help over the winter ...