How to Prune Overgrown Rhododendron?

Cut back the plant to expose the inner branches. Follow the branch down to the last whorl of leaves you want to keep and cut just above those leaves, about 1/4 inch (6 mm.) above the topmost leaf in this cluster. Large, overgrown rhododendrons can be cut 12 to 15 inches (31-38 cm.)

How far back can you prune rhododendron?

Depending on how big the rhododendron is, you may be able to cut back 15 to 20 inches of each branch of the plant. Because the rhododendron species are not meant to be cut in a shape, each primary branch that you cut should be cut at different heights to make the shrub appear natural.

Can you hard prune rhododendron?

Should you have an old, established rhododendron that needs to be given a new lease of life, heavy pruning is possible. Choose a frost-free day in February or March and cut back branches hard to one of the tiny, dormant buds. If necessary, you can coppice the plant down to around 150cm tall.