Prune Perennials in Early Summer to Extend Flowering!
Become a better gardener! Discover our new Almanac Garden Planner features for 2024. It’s easy, fun, and free to try!
What is the Chelsea chop? A new hairdo, dance craze, or fancy cut of meat? Nope, it’s just a pruning technique. By cutting back perennials in early summer, you can get better blooms, over a longer period, and stop your plants from becoming leggy! Here’s how it’s done.
The Chelsea Chop
The name “Chelsea chop” comes from the Brits because they do it around the time of the annual Chelsea Flower Show in May. However, for many areas, the timing is simply late spring or early summer. For me, it should be called the “4th of July chop,” since cutting the plants any later than that won’t give them enough time to recover and blossom before fall.
The whole idea is that one hour of pruning now would result in three more weeks of flowers at the end of their season! As well as extending the blooming season, you are controlling the growth and shape of your perennials for a better-looking, fuller, more compact plant. This pruning technique is especially suited to perennials to get too tall and leggy such as phlox, aster, and sedum.
Read Next
Photo: Time for the Chelsea chop otherwise these plants get too tall and floppy.
It’s hard to chop but it works and you’ll be happy once you see the renewed blooms! I ruthlessly chop off the top 1/3 of 1/2 of the New England asters and tall phlox in my front flowerbeds because they get so tall we can’t see out of the windows! I am a little more selective in the other beds, cutting back only about half the plants in a clump, leaving a few to grow tall and blossom earlier. The shorter ones help to support the leggy ones, lessening the need for staking, and hide their “naked ankles”, the leafless stems at the base of the taller plants.
Before: The rapidly growing asters and phlox have obscured the dark-leaved ligularia.
After: Now the ligularia has a fighting chance. I left a few tall asters near the back of the bed to blossom earlier than the newly cut plants in front.
I usually just use my trusty kitchen shears to make random sharp cuts but you can use pruners, loppers, or even hedge clippers to get the job done faster.
Before: Phlox take over in front of the shed and get so tall and floppy it can be a challenge to open the door! They also overtake the other plantings.
After: Now you can see the container that was hidden by the growing phlox plants. I left a row of tall ones in the back to blossom first. They have the shed to lean on for support and the shorter plants in front of them will hide their naked ankles.
Pink asters are in short supply in my garden so I take advantage of the opportunity to make more.
If you are as frugal as I am, save some of the cuttings to root and make new plants! New England asters and phlox cuttings placed in a glass of water will produce new roots in no time. They can be potted up to share or planted out in the garden where they often bloom the first year.
The Chelsea chop is best done on late summer or fall bloomers like rudbeckias, helenium, goldenrod, asters, phlox, marguerites, chrysanthemums, and nepeta. Since it encourages branching, the plants will be shorter, more compact, and have more flowers. By leaving a few tall ones to bloom earlier you can extend the bloom time. Give it a try!
→ Read more about growing a flower garden or caring for a perennial garden.
Robin Sweetser
ADVERTISEMENT
Would the Chelsea chop work on cup plants? I’m trying to find a way to keep them under 8’ tall, 😂
I have a New York Aster (which I believe is different from the New England Aster), that I planted last year. It is already blooming here in SW Ohio. Should I chop it as well? If so, should I wait until after all the buds have opened or do it now?
Can I cut the tops off my phlox before they have even flowered and they will still flower later?
Some of the earlier blooms on my newly set out hydrangea are turning brown. Should I cut those off and would that produce more blooms?
Definitely pick off the dead brown blossoms just to tidy up the plant if nothing else. It all depends on the type of hydrangea you have whether deadheading will encourage new flowers to form.
Where do you cut at to chop them back? Any certain way to do it?
I'm not real fussy about it since the new growth eventually hides any unsightly cuts. You can take time to carefully cut them back by half the length of the stem, making your cuts just above a leaf. Or just attack them with your clippers like I do!
Only heard the phrase Chelsea Cut this spring from a British gardening show, but I was shown years ago how to fix leggy mums with this method by a gardening mentor.
Works great!
Also, thanks for the tip of using the cuttings of asters to create new plants.
This is a good idea. Also, I love the name. But, maybe I am biased because my name happens to be Chelsea!
:)
We have a Chelsea in our family too! A beautiful name for a beautiful person!
