The Chelsea Chop is a useful pruning method that we regularly use at Larch Cottage to control the flowering times of a wide range of herbaceous perennials. Named the Chelsea Chop, as the technique is used around the time of the RHS Chelsea Flower Show in late May to early June, it can ensure a prolonged flowering season and create a more compact growth habit. At this time of year, many herbaceous perennials can be chopped back by up to a half, which will delay flowering but produce smaller, more numerous flowers later in the season, while also reducing the need for staking plants that are prone to be leggy or have a sprawling growth habit.
If you have several of the same plant, you can chop back half and leave half, or you can simply chop the front section of a plant and leave the back to flower earlier; alternatively, try chopping every other stem of the plant. Use sharp, clean secateurs and cut just above a leaf joint.
It is a very useful method in the herbaceous border, so enjoy experimenting with this technique and look forward to perennial displays that are fuller and longer-lasting this summer.
Blog post written by Jo Chamberlain