How to Prune Caucasian comfrey?
Cut back after flowering to encourage neat, young foliage

Caucasian comfrey · Symphytum caucasicum
Grow in moderately fertile, moist soil in sun or partial shade. Be aware the plant growth can be vigorous once established and has the potential to become a nuisance, so will require appropriate management
Cut back after flowering to encourage neat, young foliage