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A bigleaf hydrangea can be pruned back by one-third of its total mass, but harsher pruning will weaken the shrub and cause it to languish for a season or two.
Prune about a third of the stems a little harder down the stem to get good foliage and big flowers in summer. It might look like a very severe prune, but in actual fact, I've only taken off about two-thirds of the plant. I've left another third to grow on.
The hydrangea, which grows on old wood, doesn't need much pruning. If your oakleaf is outgrowing its dedicated space, cut back no more than one-third of the stems after the plant flowers in June or July, says Becker. Weak and dead stems can also be removed in late winter or early spring.
Oakleaf hydrangeas, Hydrangea quercifolia: This native hydrangea features cone-shaped white blooms that turn a beautiful shade of russet in late summer. It, too, blooms on old wood so should not be pruned until after flowering.
New Wood Bloomers
It is easy to grow these hydrangeas because they bloom every year regardless of how they are cared for or treated. They can be pruned to the ground in the fall and they will emerge in the spring with bountiful blooms.
4. No need to prune. If you trim your plants in fall or winter, you may mistakenly remove flower buds for the following year on bigleaf and oakleaf hydrangeas. Leaving the old flower heads on the plants will also add some interest to the winter landscape.
After a day or so of being cut, the blooms begin to wilt. About three days later, they are completely done. But guess what I just learned (from an instagram conversation)? Hydrangeas take in water from their PETALS!
While some plants bloom on new growth, others primarily set flower buds on old wood. Regardless, it is best to wait to prune all hydrangeas until spring. In the fall, hydrangeas (and all trees and shrubs) are in the process of going dormant. They do not produce very much new growth until the following spring.
If your hydrangea is too wide for the location, you can dig it up and divide the plant, or move it back away from driveways and walks. If just a few stems are hanging into walkways, follow those to the ground or where they join another stem, and cut them off.
As soon as hydrangeas are cut, the stems should immediately be put into tepid water. And adding a little bit of flower food to it would be a great idea too. Use a sharp knife or clippers to cut each stem on a diagonal and submerge! Cut hydrangeas in the morning and choose only the most mature blooms.
Are the blooms on your hydrangea shrubs fading or turning brown? No need to worry – this is simply a sign that it's time to remove the flowers, a process called deadheading. When you deadhead hydrangeas, you aren't harming the plants at all.
(3) In addition, if it becomes necessary to prune a plant to reduce its size, it may be cut back in June or July without harming the next year's bloom. But it will return almost immediately to it's former size.
So the bottom line is that if a hydrangea is too large for the location where it has been growing, the best thing would be to move it and plant a smaller variety in that spot.
Brown, tan, yellowish or black spots on hydrangea leaves may be anthracnose. You can also identify it by cankers that form on stems and branches. Anthracnose can be fatal to hydrangeas, so prune out dead or diseased plant parts and destroy them.
Some hydrangea species bloom on last-year's growth, which is often called “old wood.” This old wood contains the flower buds that will open with the coming summer. Pruning in winter or spring would remove the flower buds, leaving us with a bloomless plant this year.
You can also check your hydrangea in the fall to see if any buds are starting to push out already. If there are buds already on the branches, then it blooms on old wood. If there are not yet buds in the fall, then it will push them out on new growth the following spring.
First, add a 1/4 cup of sugar to the room temperature water in the vase. The sugar helps feed the stems and increases the life of the cut flowers.
Hydrangeas will wilt or start drooping when they cannot get the water that they need. That's when you can try reviving them by giving them a nice cool bath in the sink! Hydrangeas are one of the few flowers that can absorb water not just through the stems, but also through the leaves and the blossoms.
In addition to encouraging hydrangeas to produce more flowers, pruning these shrubs each year helps keep them healthy if they get damaged by weather and allows you to shape them however you like.
To reduce the size of a hydrangea that blooms on new wood, cut off about one-third of each stem in late fall or early spring before it begins to leaf out. If your hydrangea blooms on old wood, prune right after it has bloomed when the flowers are fading.
Without going through the deadheading process, hydrangeas will not produce as many flowers and the few produced may not grow as big to their full potential.
But when to prune them? Prune fall blooming hydrangeas, or old wood bloomers, after they bloom in the summer. If you prune old wooded hydrangeas in fall, you are cutting off next seasons blooms. Summer blooming hydrangeas, or those that bloom on new wood, are pruned in the fall, after they stop blooming.