Decades ago, while I was spending my time chasing little white balls on the golf course, a knowledgeable golf pro gave me a piece of invaluable advice.
“If you go to a professional for lessons and they give you a list of 15 ways to improve your swing, you're not really taking lessons,” he says.
His argument was simple: For a weekend golfer, it's more effective to make one choice at a time than to try to improve 12 things at once.
The same goes for gardening.
For some people, the hurdles of gardening are simple, but pretty low: 1. Buy a plant. 2. Plant the plant. 3. Give the plant a little water every now and then. 4. Check to see if the plant is still alive after a year.
Now, there’s nothing wrong with this model. Some of us might prefer to spend all our waking hours fulfilling the unreasonable demands and desires of a rare Daphne planted in an unsuitable climate. But it’s natural for planters to also want to occasionally go to the movies, have happy hour with a few friends, or go on a picnic on a lovely summer day.
I don't know any such people, but I'm sure they exist.
But this article is for people who have mastered the basics and are ready to level up, not for the single-minded type of person who thinks about nothing but plants. The Chelsea Chop is one of those easy-to-manage gardening techniques that can help you take your gardening to the next level.
What is the Chelsea Chop?
The Chelsea Chop is the practice of pruning back the shoots of perennials and annuals by 1/3 to 1/2 to prevent overgrowth and stem length and to alter the flowering and growth characteristics of the plant. The name was coined by our friends in the British horticultural community because it is most commonly performed in late spring, around the time of the Royal Horticultural Society's famous Chelsea Garden Show. Here in Kentucky, we sometimes call it the Post-Derby Chop.
How does the Chelsea Chop work?
Whatever you call it, pruning in late spring to early summer puts basic plant physiology to work for the gardener. In most plants, as a shoot grows to produce new leaves and buds, cells at the growing tip produce a type of plant hormone (auxin) that flows back up the stem and inhibits lower buds from opening up and producing new shoots. This is called apical dominance. But cutting back the stem and removing a group of auxin-producing cells at the tip of the shoot reduces the levels of auxin that flows back up the stem, allowing lower buds to open up and form new shoots.
A good Chelsea chop has two effects. First, it releases previously suppressed buds and produces more shoots, resulting in a shorter, more branchy plant. The plant will grow bushier, but not as tall. Chopped plants will flower more prolifically, but with smaller flowers. Second, the Chelsea chop tends to delay flowering, as the chopped plant reorganizes its resources and returns to activity.
As a variation on the theme, some specimens can be Chelsea chopped and others left uncut to spread out the flowering period (cut plants will flower later and uncut plants will flower earlier), or the front stems of the clump can be cut and the back stems left uncut. Some perennials, such as cat mint (Nepeta species and varieties), can be cut after flowering to encourage a second bloom.
What plants can you Chelsea Chop?
Generally (and remember that this will require some experimentation, as the only absolute rule in gardening is that there are no absolute rules), the best candidates for the Chelsea Chop are plants that flower in late summer or fall. Many spring-flowering plants, especially those that bloom very early, tend to have flower buds formed underground the previous fall. Plants such as daffodils, peonies, and irises don't make good candidates.
Many late-flowering plants have not yet formed flower buds underground to overwinter. Most of these plants produce new shoots and leaves from their growing tips, and at some point in the season (usually in response to changing daylight hours), the shoot tips switch and change from producing leaves to producing flowers. These are perfect candidates for the Chelsea chop. Fall-flowering asters, chrysanthemums, and butterfly bushes are some great examples.
Another group of candidate plants are shrubs and herbaceous perennials grown primarily for their foliage. Purple smoke bush (Cotinus coggygria cv.) and ninebark (Physocarpos opulifolius cv.) have really pretty flowers, but their main draw in the garden is their vibrant foliage. If you give them a liberal dose of Chelsea chop at this time of year, they may produce fewer (or no) flowers, but you'll get a more compact plant that continues to produce bright, fresh foliage.
Another way to use Chelsea chop in your garden is to control your annuals. Whether they're the vibrant leaves of coleus or the billions of flowers of lantana, cutting them back every now and then will keep them from growing too tall and collapsing after a midsummer thunderstorm. Another added benefit is that by reducing the amount of water-loving foliage, you can reduce the need for watering.
Whatever your motivation, the Chelsea Chop is a great next-generation tool to help you get more out of your garden, so give it a try!
