How to prune sedum 'autumn joy'

Early spring (March) for main cutback; Chelsea Chop in late May to reduce height. In early spring cut all stems to 5–10 cm above the ground. For a Chelsea Chop, cut the front half of the clump back by one-third in late May to stagger flowering and reduce floppiness.

Annually in spring; optional Chelsea Chop every 1–2 years. Sedum 'Autumn Joy' (Hylotelephium 'Herbstfreude') benefits from cutting back in early spring and optionally Chelsea-chopping in late spring to keep plants compact. Leave the dried seedheads over winter — they provide structural interest and shelter for insects. Cut the whole plant to within a few centimetres of the ground in March.

In early spring cut all stems to 5–10 cm above the ground. For a Chelsea Chop, cut the front half of the clump back by one-third in late May to stagger flowering and reduce floppiness.