Anita Morton - Growing Gardens
There are some plants that attain almost mystical status among those interested in natural health or organic gardening. One such is comfrey (Symphytum officianale), a plant with numerous claims made about it, including healing properties, ability to promote composting and virtues as a plant food.
Im not qualified to prescribe or promote any plant, but I will say that Ive used a comfrey leaf poultice on a sprained ankle, and it did seem to help. If you are interested in the use of this or any other plant for medical purposes, I recommend that you consult a qualified herbalist first.
Were on safer ground when it comes to garden use. Comfrey leaves are often touted as a compost accelerator that is, they speed up the decomposition process. If given ideal conditions, comfrey produces lots of juicy foliage that is ideal fodder for the compost heap. I cant say that the decomposing effect is very noticeable; you will probably find that having a good big heap, keeping it moist, and turning it regularly will produce good compost whether you add comfrey or not.
Comfrey leaves make a tonic for tomatoes, capsicums and chillies when rotted down in water. The resulting brew is smelly, but is said to contain good levels of potassium (potash) which these plants require. Its worth a try if you have a flourishing comfrey clump.
This plant needs a moist situation and quite a lot of shade in our hot climate. If you enrich the soil with compost, comfrey will produce lots of leaves for the compost or plant tonic, chicken fodder, or just to use as mulch. Be warned the plant is difficult to get rid of once established, as it will regrow from any fragment of root left in the ground. Be sure you want comfrey before you plant it!