The care you provide your hydrangea throughout fall and winter directly affects its performance during the next growing season. Winter takes a toll on this plant, so it's important that the roots are insulated from freezing temperatures and the branches protected from damaging winds. Hydrangeas are fairly hardy, but without the proper protection during winter months, summer flowering will be minuscule to non-existent.
Stop fertilizing in late August. This will direct nutrients toward the roots instead of promoting new growth.
Prune off all old wood found at the plant's base in late summer. Remove all damaged and dead branches, taking care not to clip off any that appear to be healthy, as this is where next season's blooms will come from.
Reduce watering in late fall, adding just enough to moisten the soil whenever there is a lack of rainfall. Stop watering completely when the ground begins to freeze.
Place four to six wooden stakes around the hydrangea. The stakes should be 4 to 5 inches taller than the plant.
Wrap a piece of burlap around the plant and staple securely to the stakes.
Place 4 inches of organic mulch on top of and around your hydrangea. Add a layer of straw and several evergreen branches, such as fir or pine, on top of the mulch.
Remove the stakes and covering from your hydrangea once the ground starts to thaw and all danger of frost has passed for your area. Leave a 2-inch layer of mulch in place around the roots of the plant.