Fancy a quick, easy way to extend the flowering period of your summer borders for free? Then a pruning method that’s been branded as ‘the Chelsea chop’ could be your answer. So called because it’s carried out in Chelsea Flower Show week (late May), as well as delaying flowering, it also makes your plants more compact, produce more numerous blooms, and negates any staking requirements, too. All in all, it’s a pretty handy trick to keep up your horticultural sleeve.
So, how do you go about this deliberate decapitation? It’s really quite simple – but you need to be feeling brave to do it. Faced with a sea of lush stems, it takes a leap of faith to then chop them back with shears to half their height, but trust us, that’s all you need to do. Ensure your tools are sharp, make the cuts and then rake up and compost the stems – or use them for softwood cuttings. Faced with a large clump, try cutting back half the number of stems only. That way the uncut shoots will flower first, then the pruned ones will follow on shortly.
Many plants are happy to be cut back in this way, especially herbaceous perennials. Phlox, rudbeckias, echinaceas, heleniums and sedums are all happy to go under the knife. The Chelsea chop should, if we’re being official, be a term only applied to these late flowering perennials. However, there’s nothing to stop you applying it to early flowering plants, too. Hardy geraniums, centaurea, alchemilla and aquilegias can all have their blooms delayed by cutting the shoots back – just jump in during the first two weeks of April instead.