Perennials to Cut Back Now for a Second Flush of Blooms – and The Ones to Leave Alone

A relaxed seating area is surrounded by flower beds filled with yellow and blue perennial plants at the Chelsea Flower Show.

You may think it's an inevitable slow decline after summer-flowering perennials peak in midsummer. However, when you cut back perennials in August, you can encourage a vibrant second flush of blooms to enjoy.

The likes of hardy geraniums, nepeta, delphinium, astrantia, and lady’s mantle can be coaxed into bonus fall flowers by being cut back in late summer. At a time when even the best perennials can start to look faded and tired, don’t just deadhead but cut the plants back hard. It may feel counterintuitive, but the rewards are worth it.