Hydrangeas generally need very little pruning. However, there are times when a good prune will be helpful. Here are 5 reasons to prune hydrangeas.
- Damaged and Diseased Stems. Always prune out damaged or diseased stems. Many hydrangeas that bloom heavily (particularly on long stems) will get weighed down from heavy rain, or blown around by strong winds, and you may see snapped or bent branches. You may also notice branches that are crossing and rubbing against each other. This will quickly cause the bark to become damaged and could lead to disease. Damaged and diseased branches should be pruned as soon as you notice them. Prune below the damaged/diseased areas and just above another branch. You can do this at any time of year.
- Dead Branches. Dead branches should be removed at the base each year. It’s often easiest to do this in the spring just as new growth is starting. You’ll be able to tell which branches are dead by the color (they’re often grey or light brown), the lack of green buds, and the fact that they will snap when you bend them lightly (live branches will bend, rather than snap off).
- Rejuvenation. After a few years, many hydrangeas start to get a little overgrown. If this happens, you can cut about ¼ to 1/3 of the older stems down to the ground. Don’t worry, the shrub will come back next year stronger than ever! It’s best to do rejuvenation pruning in the summer.
- Size Reduction. Most hydrangeas can be cut back to control growth for the current growing season. But be aware that hydrangeas will quickly grow back to their former size. Each hydrangea has a mature size that’s genetically programmed into it – no matter how much you prune, the shrub will always try to grow back to that pre-determined size. The best option is to plant the right hydrangea in the right place. Look at the plant tag when buying hydrangeas to see what the mature size (height and width) will be.
- Shape. Sometimes you’ll find that hydrangeas start to look a little lopsided, are growing in the wrong direction, or a just not quite the shape you’d like them to be. You can prune hydrangeas to shape them, but they often grow back fairly quickly. Pruning for shape is best done with panicled hydrangeas (Hydrangea paniculata) that are grown as a tree-form – this can be done any time of year except summer.