Wintering Hydrangeas – Healthy Through the Cold Season

Different hydrangeas have different needs when the cold season sets in. Some can tolerate a few sub-zero temperatures, while others require a warm winter home.

It's simple to let winter-hardy hydrangeas overwinter. Gardeners only need to worry about young plants that have recently been added to the garden. For these, prepare a bed of foliage on the ground. Older, well-established plants are equipped with sufficient internal frost protection. This is the case for Bigleaf, Snowball, and Panicle Hydrangeas.

This rule applies in "normal" cases, meaning at temperatures up to -10 °C (14 °F). In a harsher winter, you should overwinter hydrangeas by covering them with warming material. Mulch is always a good choice, but brushwood branches and foliage also do a great job.

More sensitive types and young hydrangeas should always be covered by the caring gardener during the cold season. The protective layer can be several centimeters thick. The plant itself can benefit from a wrap of jute or fleece. If you want to overwinter your hydrangeas particularly carefully, build a wire or wooden frame around them and pad it with leaves. Such a hydrangea bed is also a good tip for potted specimens. In all cases: don't underestimate a late frost! If you've removed the warming materials after successful overwintering, you should quickly bring them back.

For balcony and patio hydrangeas, you can overwinter older plants by moving them close to the house wall. Wrap their containers with jute, fleece, or plant film and place them on a wooden base, as the root system should always be protected from the cold.

Now, you need to prevent the plants from drying out. Regular checking and watering ensures you can successfully overwinter your hydrangeas. But make sure there's a drainage hole to prevent waterlogging. Hydrangeas generally don't like this, and it won't get better in the cold winter!

As a rule of thumb: the smaller the pot, the more sensitive the plant. A diameter of at least 30 centimeters (approx. 12 inches) is recommended. Young and sensitive hydrangeas belong in a greenhouse with shading options, in the cellar, or in the garage. Do not bring them into living spaces unless they are designated indoor hydrangeas! Young hydrangeas need temperatures between 3 °C and 9 °C (37°F and 48°F) and dark rooms for their dormancy. They also don't want to dry out and require moisture control.