The best time to prune a common hydrangea (Hydrangea macrophylla) is spring, once all chance of frost has passed. Common hydrangea is pretty hardy but it can get some frost damage in very severe winters. In spring, you can cut any frost damaged branches right back to the living wood.
Common hydrangeas flower on the previous year’s growth (so not branches grown this year). Regular pruning of hydrangeas ensure nice and abundant flowering. Most pruning should take place in late winter/early spring but the climbing hydrangea should be pruned after summer.
If a common hydrangea gets too big, you might need to cut it back fairly drastically. This means pruning the entire common hydrangea’s branches right back to 30-50 cm height. New branches will then grow on your shrub throughout the year.
The newest varieties of common hydrangea (Hydrangea macrophylla) flower on both old and new wood. After a winter pruning, the bush will grow new branches that will flower that same year. Common hydrangeas are all labelled individually to indicate exactly which you have – one that flowers on old wood, or a common hydrangea that flowers on new wood.
Rejuvenating common hydrangea
It’s even possible to rejuvenate common hydrangea (Hydrangea macrophylla) that have been in the garden for years – you can do this over a period of 3 years and then it will be completed rejuvenated. Here’s what to do - Every year, cut back 1/3 of all the branches to 30-50 cm. The following year, do another different 1/3 of your hydrangea branches, and so on.