Maintenance Pruning Hypericum For Shape And Rejuvenation With Peter Lickorish
Elizabeth is a Permaculture Garden Designer, Sustainability Consultant and Professional Writer, working as an advocate for positive change. She graduated from the University of St. Andrews with an MA in English and Philosophy and obtained a Diploma in Applied Permaculture Design from the Permaculture Association.
Reviewed By PETER LICKORISH
Peter is a Horticulture Lecturer and self-employed Horticulturist, with a passion for diverse areas of the industry - from garden design to the science behind plant growth and propagation. He has completed the Royal Horticultural Society’s Master of Horticulture (MHort) Award and lectures on RHS courses at Bedford College.
IN THIS GUIDE
Hypericum is a varied genus, containing a wide range of different plants.
They can be annuals or perennials, shrubs or trees and can be either evergreen or deciduous.
Many of the hypericum most commonly grown in UK gardens are shrubs and one of the things to think about when growing shrubs is whether they should be pruned, and if so, how and when.
Shrub-type hypericums typically fall into RHS pruning group 8, so they usually require little pruning.1RHS Pruning groups. (n.d.). Royal Horticultural Society. Retrieved March 20, 2023, from https://www.rhs.org.uk/pruning/rhs-pruning-groups
Most hypericum shrubs will need only a light tidying prune after flowering or a light shear over for improved shaping and regular growth, as Master Horticulturist Peter Lickorish explains:
“Hypericum is one of those plants which exemplifies that pruning is a man-made art and as such there is no particular right or wrong approach.
“The majority flower on new wood, which means as long as you avoid pruning in the 2-3 months before flowering, you can cut back to achieve what you want from the plant.”
Some more vigorous growers, such as Hypericum ‘Hidcote’, can be pruned back harder and old shrubs that need rejuvenation can be cut back hard, close to ground level, in spring.
Maintenance Pruning
Most hypericum shrubs will only need to be tidied up and given a light prune just after they have finished flowering.
Dead, damaged or diseased material should be removed, and you can cut back a little to keep the shrubs in shape and looking good.
“Some have a habit of producing odd long, straggly stems, which can be clipped back to retain the overall shape,” shares Master Horticulturist Peter Lickorish.
You can also keep the shrubs looking good by removing up to around one-third of the older wood, though this is not essential.
After pruning, you should mulch the plants, and consider feeding them with a high-potassium organic fertiliser.
Pruning For Shape
Certain hypericums are grown as hedging or ground cover and require shaping to create the desired effect.
If you are growing your hypericums in this way, it is often a good idea to shear over the plants and prune them a little more deeply to ensure that the right effect is maintained.
Pruning Vigorous Varieties
Some hypericums are more vigorous growers and require a harder prune, whether or not you wish to keep them a particular size and shape.
Cutting these varieties back hard in spring will encourage good new growth as well as keep them attractive and contained.
“I do tend to cut my Hypericums fairly hard back in late winter or early spring, creating a framework of woody branches around 30cm high, from which a profusion of lush growth forms,” says Peter.
“For ground-cover species, I find cutting stems nearest the edge of the border to ground level, or lifting them, allows those slightly further in to arch over and soften the edge.
“Keeping this up regularly is a good way to stop it spilling over paths, whilst looking somewhat natural.”
Pruning To Rejuvenate
If you have an older hypericum shrub that needs rejuvenation, then don’t be afraid to do something quite drastic.
Prune the shrub by cutting it back hard, to just 30cm or so above soil level in the spring.
This should encourage it to put on healthy new growth.
Though they do not need it often, hypericums in general are tolerant of pruning, and can be hard pruned in spring should they get out of hand.
