How and why to chop your perennials for longer or later flowering and healthier, stockier plants

Around the time of the Chelsea Flower Show (end of May) lots of gardeners get their shears out and do the unthinkable - it’s called The Chelsea Chop.

It’s so very tempting isn’t it, to let a garden grow un-checked…I mean why on EARTH would one chop glorious, burgeoning plants just as they are about to fulfil their glorious destiny? The answer is of course that yes, it IS a crazy thing to do, especially if one is waiting patiently for a prized plant to flower, BUT there are reasons to be bonkers in the garden, and here they are:

1. Delayed gratification - Chopping a perennial in bud, or whilst it is flowering will delay that lovely event, so that in effect, you get two bites of the cherry

2. Shorter, less floppy plants - this is VERY key if, like me, you are terrible at staking (or can’t be bothered). Chopping will aid the production of more side shoots, which will give you a shorter, bushier plant.

3. Late summer abundance - Spring and summer are so lovely in themselves….everything is green and gorgeous. If you chop, then you can get some of that loveliness later on, when the garden is turning, well, BROWN and new growth is scarce.

The science behind all of this:

Plants, as we know, just want to reproduce. That’s their THING. If you bear to chop some stems before high summer hits, then they will respond to the apocalypse by producing more stems and flower (to make up for the flowers and potential seeds that have been removed.

I’d love to give you a blanket rule. When I first began Chelsea Chopping I searched and searched for lists of plants that I could chop and those I should leave alone. The nearest thing I’ve found to a comprehensive list is the truly brilliant book by Tracy Disabato-Aust The Well-Tended Perennial Garden.This book isn’t just about chopping and deadheading and pruning - there is LOTS more, including invaluable plant lists and photos galore, but it’s pretty exhaustive if you’re looking for an ‘encyclopaedia’ focusing on keeping perennials looking their best. It’s one of those books that I just keep coming back to again and again.

But as with all things in the garden, experience has shown me that I instinctively know what to do with each plant by using my common sense.

So nose around in the undergrowth and establish which plants are producing rosettes of new growth at their bases…(geranium phaeum is an example) you can chop that one quite close to the ground. Remove the flowers of other things individually (alchemilla mollis is an example of this). Other things can be given an haircut - cutting back by a quarter, third or half (look at thyme, nepeta, santolina and friends here). And late summer blooming plants (rudbeckia and the rest) can again be chopped back to stop them flopping over later. This is a tiny list, but I hope it gives you at least some idea of the possibilities.

Always always treat any plants that you butcher like this to some tender loving care in the form of deep and regular watering, along with feeding too if that’s something you do, to help them recover and give you what you want.

x Laetitia