QHow can I keep my sedum in a well-shaped clump? Denise Jackson, Tyne and Wear
AThis lovely plant is a clump-forming perennial. After three-five years the stems become overcrowded, thin and spindly, which makes the stems prone to collapsing outwards.
To encourage thicker, sturdier growth, lift and divide your plant every three-five years in spring. Grow in free-draining soil in full sun.
Sedum spectabile responds well to the ‘Chelsea Chop’. Cut back all the stems by up to half at the end of May, which will result in sturdier plants that do not require staking.
Divide sedums every few years