How to prune symphyotrichum novi-belgii 'fellowship'

Late May to early June (Chelsea chop); late autumn after flowering. Shear all stems back by half in late spring. In autumn once flowering is complete, cut the clump hard down to ground level to remove old stems.

Annually. New York asters respond well to the Chelsea chop in late spring, which reduces the need for staking and increases flower count. Cut stems back by half in late May or early June. After flowering ends in autumn, cut the whole plant to ground level to encourage fresh basal growth.

Shear all stems back by half in late spring. In autumn once flowering is complete, cut the clump hard down to ground level to remove old stems.