Author: Jm Date Posted:6 June 2018
Following on from our Heavenly Hydrangeas blog last month a customer has asked how to prune a reluctant flowering Hydrangea.
As with most shrub pruning the aim is to create a nicely shaped shrub and to promote a rounded shrub on which there is plenty of new season growth on which the plant flowers.
This process can be split into roughly five steps:
Remove all of the old flowers so that you can assess the situation.
Identify the three types of wood on the rest of the plant.
Ist Year Green, shiny and with white vertical markings, generally the branches with flowers or blind shoots on them.
2nd year Greyish green with slighty flaking bark with side shoots
3rd year and older Dull grey with flaking bark
Remove some of the main branches from deep within the centre of the bush with either loppers or a pruning saw. The branches that need removing have old and flaking bark right in at the base of the plant .
Take all stems that have had flowers on them the previous season to blind buds further down the stem and spur back any new water shoots that might be coming from the base of the plant. This will create an open structure on which there are plenty of new flower bearing shoots next spring.
If there are additional pieces of very old wood at the base of the plant that maybe should be removed to make way for new growth then tackle them also.
Over time, this type of pruning will create a rounded framework with a balance of sturdy second year wood and vigorous first year wood rising from the base .
Hydrangeas are gross feeders so plenty of slow release fertilizer should be applied to encourage lush new growth in spring. Heavy mulching is advisable soon after the plant is pruned to preserve as much spring moisture in the soil as possible.