Chelsea chop: 13 perennial plants to pinch

What is the Chelsea Chop?

From the English verb “to chop,” and the Chelsea district in London where a famous flower show takes place at the end of May, the “Chelsea Chop” is the name given to a technique of pinching perennials traditionally performed at the end of May. Pinching refers to the action of cutting the tip of a stem between the thumb and index finger. A pair of scissors achieves exactly the same effect. This action of pinching flowers is known to gardeners when it comes to “deadheading,” which means removing faded flowers from perennials or annuals like Cosmos, for example, to encourage continuous flowering and renewal.

In the case of the Chelsea Chop, the aim is to pinch the tips of non-flowering stems that are just starting to show their first buds early in the season, to thicken the perennial plant, allowing it to grow in a straighter and more harmonious manner, giving it a lovely compact habit and resulting in a greater number of flower buds (the flowers will be smaller). The plants will not be leggy; on the contrary, they will maintain a beautiful bushy appearance with lovely proportions.

This technique also allows for the selection of stems to cut (one out of two, for example), to stagger the overall flowering time of the plant: this gives control over the duration of flowering, which is longer. The flower beds are enhanced throughout the season!

→ Discover the Chelsea chop technique in detail with Pierre.

When should you proceed?

According to the date of the English “Chelsea Flower Show,” which traditionally takes place in the last week of May, the pinching of perennials should be applied at this time, that is to say, late May. Summer perennials usually have not yet produced flower buds. This actually depends on the region and climate, as well as the progress in the growth of the perennials… Intervention should occur when the plants have already developed well, otherwise, there is a risk of having the opposite effect and weakening the plants.

Therefore, the Chelsea chop can be adopted until mid-June for the later perennials, such as Asters or garden Chrysanthemums, for example. The later you pinch, the more you delay the flowering of the perennial that needs to produce its flower buds.

What are the ideal plants for the Chelsea chop?

The Chelsea chop is beneficial for summer and autumn perennials that are tall and/or have generous flowering and strong floral development. This technique allows these types of plants to become bushier and denser, strengthening their stems so they can more easily support the weight of the inflorescences, as seen with Phlox, for example. This helps to avoid staking a number of plants. The plants in question are herbaceous perennials, referred to as “soft,” meaning they are not woody.

Here is our selection of perennials that benefit most from pinching:

SUMMER PERENNIAS

• Penstemon

To maintain their attractive appearance, apply the Chelsea chop to Penstemon, these lovely perennials often found in a wide range of pink hues. They will be even more floriferous, knowing that you can renew their flowering throughout the summer by stimulating it again by cutting back the faded inflorescences.

Penstemon

• Campanula

With their bell-shaped flowers in pink, mauve, or white, campanula delight us in summer. By adopting the Chelsea chop on these romantic perennials, you will better control their flowering to spread it over time.

Campanula

• Salvia

Salvias also benefit from the Chelsea chop, which helps them maintain a more bushy habit. Try it on Salvia nemorosa, for example. However, shrubby salvias, which tend to be woody, should be treated with a spring pruning, or even late winter depending on the region.

Salvia ‘Amistad’

• Phlox

With a little help from the Chelsea chop, you will encourage a more abundant floral induction in Phlox, these charming, slightly old-fashioned plants that look stunning in all types of gardens. Varieties with very large flowers will also suffer less from summer rains and gusts…

Opulent and highly flowering Phlox

HIGH PERENNIAS

• Leucanthemum

Large daisies or Leucanthemum, often reaching nearly 1 metre in height, will particularly benefit from the Chelsea chop applied to half of the stems to prolong their generous flowering.

Leucanthemum

• Helenium & Rudbeckia

Heleniums bloom in summer until September, gracing us with their beautiful flowers in warm, spicy colours. They benefit from pinching to stand upright, as most of them are quite tall. Rudbeckia, also part of the aster family, recognizable by their yellow flowers with black centres, are also great fans of the Chelsea chop.

Heleniums

• Perennial Helianthus

Perennial Helianthus, commonly known as sunflowers, in pale yellow to golden yellow, are other tall plants. They are also enhanced by late spring pinching.

Helianthus giganteus ‘Sheila’s Sunshine’

LATE-FLOWERING PERENNIAS

• Asters and Chrysanthemums

Asters and chrysanthemums brighten the garden when it begins to fade. Their delicate flowers will be even more numerous, and their appearance controlled by a Chelsea chop in early to mid-June, when they start to develop.

Asters and Chrysanthemum

• But also:

Other beautiful blooms await us for late summer: they will also benefit from a little Chelsea chop to further stagger their flowering and maintain a compact habit for plants that might otherwise tend to open up too much: the Solidago (goldenrod), autumn Aconites like Aconitum carmichaelli and all Sedums (stonecrops).

Solidago, Aconitum carmichaelli and Sedum

Learn more about the Chelsea Chop...

Join Olivier in his video where he explains the Chelsea chop and its many benefits through demonstration!