Technically, Hydrangeas do not have to be pruned. They only need to be pruned if they have grown too large for their space and are becoming an eyesore. If your hydrangea is in fine shape, it may just need a little tune up by deadheading spent blooms and dead branches.
When’s the right time to prune? The best time to spruce up your hydrangea blooms depends if your hydrangea blooms on new or old wood. Hydrangeas that bloom on old wood, start producing buds soon after blooming. It’s essential to prune them just as the blooms begin to fade in mid-summer. The longer you wait, the likelier it will be that you’ll cut off some of next year’s growth. If your hydrangea blooms on old wood, first remove any dead limbs, then crossing branches, followed by thinning out the interior of the plant to open it to more sunlight.
Hydrangeas that flower on new wood, have buds that are set within the season, so the shrub should be pruned in early spring before the new growth emerges. If your hydrangea blooms on new wood, the plant can be selectively pruned. Choosing branches that don’t conform to the desired shape of the plant or to just control the size. Certain types of hydrangeas such as Anabelle’s can receive the most severe reforming, with the entire shrub being cut back to six to 12 inches above the ground.
Below are the most common type of hydrangeas. We’ve listed information about when they should be pruned and whether you should winterize them:
● Big-Leaf hydrangeas are the most common type of species and include the popular mop-heads and lace caps ranging from blue, violet, pink, purple, red and white. These bloom in early summer on old wood, so they should be pruned after flowering. Big-Leaf Hydrangeas need to be winterized. See below for the best way to winterize them.
● Oak leaf Hydrangea is a native hydrangea that features cone-shaped white blooms that turn a beautiful shade of russet in late summer. Oak leaf Hydrangea also blooms on old wood and should not be pruned until after flowering. Oak leaf Hydrangeas need to be winterized. See below for the best way to winterize them.
● Panicle hydrangeas, are often pruned as tree forms, these shrubs explode with panicle-shaped white flowers in mid- to late summer. They bloom on new wood; panicle hydrangeas should be pruned in early spring before they sprout new foliage. Panicle’s do not need winter protection unless the temperature drops below 5-10 degrees. If you live where temperatures drop below this range, see below for winterizing tips.
● Hydrangea arborescens ‘Annabelle’ feature globe-shaped blooms in spring that start out chartreuse and later turn white. This variety of hydrangea blooms on new wood as well and should get pruned in early spring. Annabelle’s do not need winter protection unless the temperature drops below 5-10 degrees. If you live where temperatures drop below this range, see below for winterizing tips.
It is best to start with a frame around the hydrangea. A frame can consist of stakes in the ground surrounded by chicken wire or burlap. After you surround the plant with its frame, you will want to insulate the plant. You can use a variety of material for insulating including oak leaves, pine straw, or something similar. Always take care when placing the insulating material into the frame to not break any branches that may contain a bud. As winter progresses, you will want to keep checking your hydrangeas to make sure that your insulating material has not packed down. If it has settled you may need to re-insulate or just readjust your previous insulation.