11 plants to Chelsea chop

BBC Gardeners' World Magazine

Published: Tuesday, 24 May 2022 at 9:29 am

We reveal 11 plants to Chelsea chop, to control their flowering and ensure a stunning summer performance.

Save

The Chelsea chop is a useful technique that helps control the size, shape and flowering time of certain summer-flowering plants – and late-May (around the time of the RHS Chelsea Flower Show) is the perfect time to do it.

By carrying out the Chelsea chop on your plants, you'll also encourage the production of more flowers. After you've cut back your plants, make sure you give them a thorough watering and some feed.

How to do the Chelsea chop
Find out who won at RHS Chelsea 2025

Discover 11 plants to Chelsea chop, below.

Phlox

Cut back phlox to encourage greater production of the richly scented blooms.

Achillea

Achillea is very attractive to pollinators, especially hoverflies. There are many beautiful cultivars to grow, including 'Fanal', 'Moonshine' and 'Summer Berries'.

Campanulas

Campanulas are known for their lovely bell-shaped flowers, in vivid shades of blue and purple. Cut them back to encourage more of the beautiful blooms.

Asters

Asters form a rich nectar source for flying insects, and respond well to the Chelsea chop. Asters you could cut back include Aster macrophyllus and Symphyotrichum laeve (formerly Aster laevis).

Echinacea

Another hugely wildlife-friendly plant, you'll be encouraging plenty more blooms to grow by cutting echinaceas back. Keep an eye out for slugs and snails on young plants.

Rudbeckias

Many rudbeckias can grow so tall that they risk flopping over in windy weather. Chelsea chopping them will help to restrict their height.

Sedums

Sedums are prone to becoming leggy and looking untidy. Give them the Chelsea chop to encourage a neater, more compact shape, with more flowers.

Penstemons

With their large, tubular flowers, it goes without saying that penstemons are a hit with bumblebees. Just some of the many stunning cultivars to grow include 'Sour Grapes' and 'Bredon'.

Heleniums

In the right spot, heleniums will rapidly grow skyward and often require staking. Cut them back to control their flowering height. Here's how to plant heleniums in August.

Nepeta

By cutting back nepeta, or catmint, you'll encourage a profusion of blooms to be produced later on, providing a later source of nectar and pollen for bees.

Helianthus

Not all sunflowers need cutting back. Don't cut back large, annual Helianthus, but instead go for perennial sunflowers, such as vibrant cultivars like 'Lemon Queen'.

Don't miss out this Winter

Enjoy expert advice on what to plant and grow this winter, and how to prepare your plot for the year ahead. Enjoy, 6 months for just £31.99

Subscribe now

Great gardening savings - straight to your inbox

Sign up to the BBC Gardeners’ World offers newsletter for exclusive deals, seasonal savings, and early access to special promotions.