How to prune blue blossom

Immediately after flowering (typically late spring to early summer). Trim back the flowered shoots by up to one-third with clean secateurs, cutting just above healthy buds or leaves. Avoid cutting into old, brown, leafless wood as the plant will not regenerate from it.

Annually after flowering; minimal intervention needed. Blue blossom (Ceanothus thyrsiflorus) is an evergreen Californian lilac that resents hard pruning — cutting into old wood often causes dieback or death. Prune lightly immediately after flowering to trim back flowered shoots by no more than one-third. Never cut back to bare old wood.

Trim back the flowered shoots by up to one-third with clean secateurs, cutting just above healthy buds or leaves. Avoid cutting into old, brown, leafless wood as the plant will not regenerate from it.