What Is the Chelsea Chop?
Late spring is the time for some strategic pruning and pinching of select perennial plants to help manage size, encourage more blooms, and extend flowering time later in the season. This technique, known as the Chelsea chop, gets its name from the timing in late spring, coinciding with when London’s RHS Chelsea Flower Show takes place.
When and How to Do the Chelsea Chop
The Chelsea chop involves cutting back certain perennials by about one-third to one-half in late May or early June. While it may feel drastic to remove so much of the plant, this pruning method stimulates bushier growth, helps prevent flopping in taller species, and often extends flower numbers on bushier plants. Cutting back also delays blooming, extending bloom time in the garden.
Which Plants to Cut Back
Many native plants that bloom in late summer and fall are good candidates for the Chelsea chop. Try observing which plants in your garden flop over in late summer and fall and consider pinching them next spring. When you have a large number of the same plant in an area, you can also experiment with cutting back some while leaving others (especially those in the back) to give variety of heights and bloom times.
Best Native Plants for the Chelsea Chop
Here is a list of some great native plants that benefit from a Chelsea chop:
- Anise hyssop (Agastache foeniculum)
- Asters, such as aromatic aster (Symphyotrichum oblongifolium), blue wood aster (S. cordifolium), New England aster (S. novae-angliae) and others
- Beebalm (Monarda species)
- Common wingstem (Verbesina alternifolia)
- Downy skullcap (Scutellaria incana)
- Garden phlox (Phlox paniculata), especially late bloomers like Jeana garden phlox (P. paniculata ‘Jeana’)
- Goldenrods, such as wrinkle-leaf goldenrod (Solidago rugosa) and Golden Fleece autumn goldenrod (S. sphacelata ‘Golden Fleece’)
- Ironweed (Vernonia), such as narrow leaf ironweed (V. lettermannii) and tall ironweed (V. angustifolia)
- Native sunflowers, such as swamp sunflower (Helianthus angustifolius)
- Sneezeweed (Helenium species)
- Tall tickseed (Coreposis tripteris)
- Turtlehead (Chelone glabra and C. lyonii)
