The roots are arguably the most sensitive part of the plant. Retain ground warmth from the summer by putting down a 2-3 inch thick layer of heavy mulch, straw, wood chips or similar insulating layer.
If you live in Zone 7 or colder in the USA, try to plant your hydrangea in a sheltered location from the wind, perhaps under an over-hanging roof and certainly close to a house wall.
Alternatively, keep your hydrangea in a pot. Keep it in a cold frame over winter or perhaps one of the cooler rooms in the house.
The killer for hydrangea buds is that they often appear before winter is really over. So then they get destroyed by the next frost and no new growth may be forthcoming. One solution is to keep old mopheads on the plant from the previous summer; these help protect new flowerbuds (to some extent).
You could also cover the new flower heads to prevent frost damage if they come out too early; rubber bands and small plastic bags are the low tech method to do this. Else fleece covers or even wrapping in cellophane. Only use the covers when absolutely necessarily, the plant needs to breathe and get sun, otherwise.
If you live in Zone 7 or colder in the USA, try to plant your hydrangea in a sheltered location from the wind, perhaps under an over-hanging roof and certainly close to a house wall.
Alternatively, keep your hydrangea in a pot. Keep it in a cold frame over winter or perhaps one of the cooler rooms in the house.
The killer for hydrangea buds is that they often appear before winter is really over. So then they get destroyed by the next frost and no new growth may be forthcoming. One solution is to keep old mopheads on the plant from the previous summer; these help protect new flowerbuds (to some extent).
You could also cover the new flower heads to prevent frost damage if they come out too early; rubber bands and small plastic bags are the low tech method to do this. Else fleece covers or even wrapping in cellophane. Only use the covers when absolutely necessarily, the plant needs to breathe and get sun, otherwise.