Plate hydrangeas are much more frost hardy than farmer's hydrangeas, which gives them an advantage, especially in cold winter regions. Nevertheless, the bushes should be in a protected location and provided with suitable winter protection.
Are hydrangeas hardy and how do you protect them in winter?
Plate hydrangeas are hardy, but require winter protection in cold locations. Young plants should overwinter in a pot or cold house; older specimens should be protected with mulch and leaves. Good varieties: “Hydrangea serrata var. koreana” and “Veerle”.
Overwinter hydrangeas planted in the garden
The following applies to hydrangeas planted in the garden: the older the plant, the less sensitive it is to frost. It is better to leave young hydrangeas (especially in their first two years) in the pot or dig them up in autumn and overwinter under cold house conditions. Older specimens are mulched heavily, for which you can easily use straw, leaves and/or compost as well as brushwood or pine branches. However, it is particularly important to protect the flower buds from freezing, especially in low temperatures and long periods of frost. Otherwise the flowers will simply fail the following year.
Protection through leaf litter
A thick, dry layer of leaves offers good protection. The best way to do this is to set up a wire mesh frame around the plant and pour leaves mixed with straw into it. The wire mesh prevents the leaves from simply being blown away. You can also cover the bushes with raffia mats (€18.00 on Amazon), with leaves poured in between providing additional protection from the cold. The winter protection is removed as soon as the ground is no longer frozen in spring.
Overwinter plate hydrangeas properly in the pot
Plate hydrangeas that are grown in a container of less than 40 to 50 centimeters should not have to spend the winter outdoors. Instead, they are overwintered under cold house conditions - that is, frost-free, cool and bright - in the house, apartment or greenhouse. If you don't have a bright place available, the plant can also be moved to the dark basement if necessary - provided it is provided with sufficient light from a plant lamp. Larger pots can be left outside, but should be protected from the cold with mats, fleece or similar.
Tips & Tricks
The plate hydrangea varieties “Hydrangea serrata var.koreana”, which has excellent winter hardiness in a protected location without direct sun, as well as the pink-violet flowering cultivar “Veerle”. The latter also impresses with its strong autumn colors.
