Hydrangeas do not require annual pruning like the rest of the other shrubs, but some of the plants especially the old ones may need pruning over and over again. Hydrangeas flower mostly from mid to late summer on the preceding year’s growth and understanding whether your shrub thrives on new or old wood will help you decide when it’s the right time to prune so you can always make timely cuts. Only through this can you significantly improve their performance because pruning them at the wrong time can cause flowers not to grow.
Since all the shrubs should not be pruned at the same time due to their blooming period difference, the ones that bloom on old growth are pruned after they flower and the ones that bloom on their new growth should only be pruned on their dormant state in fall or before spring when they become alive again. The increase of the size of flowers is an indication that you pruned your hydrangeas correctly and at the right time since by doing so you improved their vigor.
Three major reasons confuse many people about how and when to prune hydrangeas, these are:
1. Failure of the shrub to bloom in summer.
2. Dead-looking appearance of the shrub in winter
3. Knowledge that shrubs require pruning
So the rest of the article will discuss the two important factors to ensure that your hydrangeas are healthy to bloom when it’s their season to flower. The factors apply to the most commonly grown hydrangeas which are the mop-heads and lace-caps (macrophyllas types usually in blue or pink), and H. arborescens which are Annabelle types and H. paniculata the PeeGee types hydrangeas. Mop-heads- easily identified by their full, large petals which have round heads while the lace-caps are characterized by small flowers that grow in the middle of the bloom, and on the outside their large petals.
Factors to consider:
1. Right time to prune hydrangeas
The period to prune mainly depends on the season and the age of the shrub as discussed earlier. Pruning is mostly done at the beginning of spring or late winter. Only the climbing hydrangea is pruned after it flowers in summer as this is the only time that it does extremely well.
2. How to prune the shrubs
There are two recommended methods for pruning the hydrangeas. The two approaches depend on what type of the hydrangeas you have in your garden, and because the stems they grow from are different, each method only applies to the respective type.
This method is for the lace-caps and the mop-heads only although there is a group of mop-head hydrangea known as the ever bloomers that bloom no matter which period they get pruned. Pruning these shrubs should be done before summer since these hydrangea types bloom on old growth. Experts believe August is the best time and that pruning them late than that might ruin them since they might have already formed their flower buds for the coming year. It is also worth noting that pruning is not the same as removing the dead blooms.
- Remove the dead stems from the shrubs every year.
- If the plant is five years or older, only two-thirds of the plant should remain and the rest cut down every summer. It revitalizes the plant.
- Consider pruning the shrub in June or July especially when your main aim is to reduce its size. It ensures you do not harm the coming year’s bloom.
This method only applies to the Annabelle and the PeeGee (PG) hydrangeas types. The hydrangea blooms on new growth, and it has been discovered that growing these species has an advantage over the rest since they do not require any special treatment and they bloom every year. The only time they like to be left alone is summer for the PG and spring for the Annabelle since this is the time that is getting ready to bloom.
- Remove the dead wood before spring or when they are dormant.
- Prune them to a framework of only branches, and it’s done annually.
- Hard prune down to the last healthy buds. In return, this will produce large flower on the strong, upright branches.
The important fact with pruning hydrangeas is knowing what type you have in your garden. Most of the hydrangea species commonly grown do not require much work and their general maintenance lies in removing the straggly, and weak stems so that when the hydrangea blooms they do not fall.