Buddleias are popular and easy going shrubs that are a favourite with butterflies, hence their common name, the butterfly bush. They come in a range of colours, from white to magenta dark purple. Some are compact and can be grown in pots and containers.

To keep buddleias flowering well every year, they need to be pruned correctly. After cutting back all the stems you will be briefly left with an unattractive stump, but not cutting it back could result in a shrub that is 3m tall with a solitary flower at the tip and lots of unsightly, brown spent flowers from the previous year, similar to those found growing on railway embankments.

Pruning buddleia

When to prune buddleia

Most buddleias including Buddleja davidii and Buddleja x weyeriana should be pruned in spring, from late March to mid-April. Buddleja alternifolia is pruned in early to midsummer. Buddleja globosa does not need regular pruning but can be cut back in late winter to keep it in shape (bear in mind that this will affect flowering the following summer).

How to prune buddleia

Pruning Buddleja davidii

The stems of Buddleja davidii should be cut right down to the base.

  • Cut just above the first shoot at the bottom of each stem, leaving a woody clump.

Even by the end of a single season the stems can be thick and woody, so you will need loppers or a pruning saw rather than a pair of secateurs.

Pruning Buddleia alternifolia

Buddleja alternifolia is pruned differently. It flowers on stems that have grown the previous year, so removing these stems in the spring would leave you with no flowers. As soon as its flowers have gone over in early to mid summer, follow down along the stem and cut just above a new shoot.

Read more on pruning:


A former nurseryman, John now spends most of his time nurturing his own garden in the foothills of the French Pyrenees. He is Gardens Adviser to Glyndebourne and currently has gardening projects in the UK, Spain and France.