Rhododendrons are a garden favourite for their bold, vibrant flowers, but many gardeners unknowingly make mistakes that prevent them from blooming year after year. According to gardening expert Michael Griffiths, the most common error is pruning at the wrong time.
Griffiths, who shares advice on TikTok, explains that pruning rhododendrons immediately after they finish flowering is crucial. He says: 'If you want bigger blooms on your rhododendron next year, a quick prune after flowering will keep them in shape and ready to thrive.' Pruning too early or too late can sacrifice the following year's flowers.
When the blooms fade, gardeners should remove spent flowers by cutting just above a pair of leaves. It's important to avoid cutting into the woody part of the stems, as this can prevent new buds from forming. Griffiths advises: 'First of all, make sure the flowers are faded like these and then remove any spent blooms to just above a pair of leaves.'
Another mistake is over-pruning. The Royal Horticultural Society notes that rhododendrons generally require minimal pruning, mainly removing dead wood and deadheading. Gardeners should also remove any leggy or dead branches to allow the plant to breathe and encourage new growth.
Finally, be careful not to knock off or cut new buds while pruning. With the right technique, Griffiths says: 'Now you've got a compact shrub that'll be loaded with blooms next season.' For late winter, experts at Gardeners' World recommend removing any dead or damaged wood while the plant is dormant.
