Pruning climbing hydrangeas is important: With our expert tips you can encourage new flowers and free the hydrangea from old shoots.
The climbing hydrangea (Hydrangea petiolaris) is a true climber. In old age it can reach heights of 15 meters and grow up to 5 meters in width. In order not to get out of shape, sometimes only the pruning shears can help. But pruning measures are also necessary for lush flowers and the good he alth of the climbing plant. This article will tell you the best way to do this.
Why should you prune the climbing hydrangea?
Since the climbing hydrangea grows quite slowly in the first few years and does not produce any flowers until the fifth to eighth year, it does not have to be pruned regularly during this period. Only in old age can it climb up to one meter per year in good site conditions, which can lead to the climbing beauty getting out of shape or carrying too much weight on one side.
Then you should prune your climbing hydrangea, but weak shoots that are too dense, dead wood and dried flowers are also good reasons for using secateurs. In this way you can create space in the flowering shrub and free the plant from unnecessary ballast. This is important because an airy shrub with a drier microclimate means that fungi are less comfortable and the risk of fungal diseases is reduced. Removing deadwood also reduces the risk of fungi, as the spores can otherwise find a good place to survive in the wood. Cutting away the unnecessary ballast protects the plant from falling over and prevents shoots from breaking off unintentionally.
If the luxuriant flowering dwindles over the years, a so-called rejuvenation pruning can also be carried out on the climbing hydrangea. The main shoots are radically shortened, which means that the flowering shrub has to sprout again and sleeping eyes wake up again. Sleeping eyes are understood to mean buds that were created in earlier years, in the then young shootand now be stimulated to develop by the cut.
Tip: It is best not to trim young climbing hydrangeas in locations endangered by late frost at all, or if only in late summer, with scissors, otherwise the cuttings could freeze back too much.
An overview of why you should prune the climbing hydrangea:
- When the climbing hydrangea grows rapidly in old age
- To remove deadwood and shoots that are too close together
- To perform rejuvenation pruning and encourage new blooms
When should you prune the climbing hydrangea?
The climbing hydrangea blooms on last year's wood. This means that in autumn, after flowering, she creates the flowering plant for the next year. The distinction as to whether a shrub will flower in the same year or in the previous year is very important, because the timing of the cut depends on it. It is best to cut back the climbing hydrangea immediately after it has bloomed, i.e. before the new flowering plant. This prevents the buds that have already formed from being cut away and from not blooming in the following months.
But you can also use garden shears in spring. The so-called need cut can be carried out from February to March. Everything that disturbs and robs the plant of unnecessary energy can be removed. These include dead wood, dried flowers and weak or disturbing shoots. The rejuvenation cut can also be done in spring. This pruning is more radical and is therefore only carried out every four to five years - or when the flowers are becoming less splendor or the climbing plant is growing too much for you.
Tip: Since climbing hydrangeas create their flowering plants in the previous year, they belong to pruning group 2 among hydrangeas. These include the peasant hydrangea (Hydrangea macrophylla), the plate hydrangea (Hydrangea serrata ), the velvet hydrangea (Hydrangea sargentiana ), the oakleaf hydrangea (Hydrangea quercifiolia) and the giant leaf hydrangea (Hydrangea aspera macrophylla). Hydrangeas, which develop their buds just before flowering, can be cut back in the spring without much caution and belong to thePruning group 1. This includes snowball hydrangea (Hydrangea aborescens) and panicle hydrangea (Hydrangea paniculata).
How to cut off climbing hydrangeas, how much?
You need sharp pruning shears to cut back. With this, after the climbing hydrangea has bloomed, the old inflorescences are removed and the shoots are cut off just above the first pair of buds. Make sure the cut edges are clean so that the plant can heal better. Deadwood or disturbing shoots can be cut off just above their source when pruning is necessary in spring. If a rejuvenation pruning is necessary, the main branches are cut back to a length of up to 2.5 meters in the spring. If the branches are a bit thicker, you can also use pruning shears or a saw. But be careful not to radically cut back all the branches at once, otherwise there will be no flowering next year. Instead, you can prune a few branches heavily over a few years.
Tip: Does your plant climb up the wall of the house? Then keep an eye on shoots that grow away from the wall. These should be cut back regularly, otherwise their weight can pull the climbing plant away from the wall over time. Other hydrangea species also need regular pruning. In this special article, we have summarized for you what you generally need to consider when pruning hydrangeas.