It is easy to become confused about how to prune hydrangeas, and there are a number of reasons for this. First is down to their dead-looking appearance in winter - just where do your start? Second, is a hydrangeas failure to bloom in summer - should you have pruned it last year? And third is because it is a shrub that absolutely thrives on being correctly pruned. In fact you can go as far and say that - get your pruning technique right - you can improve the vigour of most hydrangeas and increase the size of its flowers.
The trouble is that if they are happy where they are and performing well, hydrangeas can live a long, floriferous life without ever feeling the cold blade of a pair of secateurs. Get it wrong though, and you can end up with a year without flowers.
Most pruning on Hydrangeas is carried out in late winter or early spring. However, the climbing hydrangea - Hydrangea petiolaris, is pruned after flowering in summer.
Ideally, remove the dead flower heads in early spring, cutting back to the first strong, healthy pair of buds lower down the stem
Lacecap varieties are hardier, and the old flower heads can be cut back after flowering to the second pair of leaves below the head in order to prevent seed developing. If the seeds develop they will saps energy from the plant which will reduce its ability to provide a decent display of flowers the following year
Pruning established mopheads and lacecaps
In fact, you may be surprised to know that poor or neglected plants can be entirely renovated by cutting off all the stems at the base.
However, this will remove all the flowers for that summer, and the new stems will not bloom until the following year.
Be that as it may, this is normally a fair price to pay.
Pruning climbing hydrangeas
Most of their flowers will be produced towards the top of the plant, so try to leave as much of this wood 'un-pruned' as possible.
Established plants will tolerate hard pruning in spring, but avoid extensively cutting back all in one go as this is likely to reduce flowering for the next couple of summers.
To prevent flower loss, stagger drastic pruning over three or four years, reducing the size of the plant gradually.
Pruning other hydrangea species
Hydrangea serrata can be pruned in the same way as mophead and lacecap hydrangeas
Each spring, cut back last year’s stems to the lowest pair of healthy buds, creating a low framework of branches.
This usually results in a pruned framework of no more than 10 inches high but, if more height is required, cut to about 2 ft tall instead.
Most other hydrangea species, including H. aspera, H. quercifolia, H. sargentiana and H. villosa, need only minimal pruning in spring to remove dead and over-long stems.
For related articles click onto:
HOW TO GROW HYDRANGEA
HOW TO PRUNE CAMELLIAS
HOW TO PRUNE HYDRANGEA
HOW TO TAKE HYDRANGEA CUTTINGS
WHICH ARE THE BEST BLUE-FLOWERING HYDRANGEAS?
WHY HAS MY BLUE HYDRANGEA TURNED PINK?