If your hydrangeas are growing lush but not flowering, you are almost certainly wrong about pruning. It is the most common mistake and also the most harmful: cutting when the plant has already formed buds means eliminating them before they can even open.
Why Hydrangea macrophylla is different from the others
Hydrangea macrophylla blooms on the previous year’s branches, called “old wood”. This means that the summer flowers are already ready, in the form of buds, during the winter. If you intervene with shears during that period, you are canceling future flowering.
The right time to prune
The correct period for pruning is immediately after the end of summer flowering, between late summer and early autumn. At this stage the plant still has time to produce new branches which will mature and bear flowers the following year.
In winter and spring the buds are already formed on the branches. Cutting them is equivalent to directly eliminating the summer flowers. The result is a green, healthy, strong plant, but completely sterile from an ornamental point of view.
When is it better to do nothing
If you have pruned badly in recent years and have not seen flowers for a long time, the most effective solution is to stop. Leaving the plant alone for a season allows you to understand if it can re-establish its natural flowering cycle.
The difference between pruning and removing dried flowers
Removing faded flowers is not true pruning. It only serves to keep the plant tidy. It should be done by cutting just above the first pair of healthy leaves, without shortening the main branch. This way you don’t touch the buds that will produce the flowers.
When to deadhead safely
The best period is between the end of winter and the beginning of spring. Alternatively, you can even not do it at all: the dried inflorescences will fall off on their own over time without damaging the plant.
How to check the size without losing the flowers
If the hydrangea gets too large, there is no need to slaughter it every year. Better to prune only a third of the branches, accepting losing the flowers on those but maintaining flowering on the rest of the plant.
The short window to reduce the plant
There is a short period, immediately after the end of spring blooms or at the beginning of summer, in which the plant can be slightly shortened. It’s before bud formation begins for the following year, so it’s the only relatively safe time to keep its size down.
With macrophylla hydrangeas the rule is brutal but simple: no pruning in winter and spring. If you want flowers in summer, you need to protect the previous year’s branches. A slightly large plant is better than a perfect but colorless bush.
About hydrangea you might also be interested in:
