Symphytum officinale

Comfrey promotes wound healing, supports skin regeneration, heals bone and reduces inflammation. Because of safety concerns it is now recommended to be used externally only. It is commonly used in topical treatments for bruises, sprains, bones injuries, aches and pains.

Comfrey is used as an organic fertiliser by soaking the leaves in water to make a liquid feed for nourishing poor-quality soil (27,28). The fresh leaves also speed up composting and can be used as mulch around other plants in the growing season (27). However, using comfrey in such a way can increase the PA content of plants in the vicinity via horizontal transfer (29). The use of comfrey in composting and as a fertiliser is, therefore, only appropriate for ornamental gardening.