March 2009 Herb of the Month - Comfrey
Symphytum officinale

Family: Boraginaceae

Comfrey is a perennial herb native to Europe and can be found growing in damp places along riverbanks and in ditches. It has large, hairy leaves and grows in a rosette to 1 m in height. The small bell-shaped, mauve or pink flowers are borne in clusters. The roots are large with black/brown skin and fleshy insides, and travel deep into the soil.

Comfrey is tough plant when grown in the right spot, it grows easily from small root pieces, choose your position carefully as it is hard to get rid of. It will grow in semi-sun or in full sun providing it gets enough water during summer. Although comfrey likes plenty of water it does not like to be in a boggy position. During summer comfrey produces masses of large leaves. During winter our garden is quite cold and the leaf growth slows to a few small leaves.

Comfrey is a must have plant for the organic gardener, its deep roots draw up a range of nutrients from the soil including silica, nitrogen, magnesium, calcium, potassium and iron. These nutrients can be accessed through the fast growing leaves, they break down quickly and can be dug straight into the soil, the C:N ratio of the leaves is lower than well rotted compost meaning no risk of nitrogen robbery when they break down.

Use comfrey leaves to activate and add nutrients to the compost heap. A layer of about 10cm thick is enough to encourage bacterial activity and create heat, always cover with a carbon layer (dry material such as brown leaves, dry brown grass or cane mulch.)

A liquid fertiliser can also be made from the leaves. Half fill a large bucket with crushed comfrey leaves. Fill bucket with water and cover securely. Stand in the shade for 4 weeks. Stir occasionally. Dilute 1part with 4 parts water. Use a watering can to fertilise plants every 3-4 weeks. (This smells really bad).

Grow comfrey on the low side of the chook pen, it will take up the nutrients that are washed downhill, as well as being a nutritious forage food for the chooks. It contains vitamin B12 and is a good source of protein. Comfrey has been used as animal forage for centuries and can be fed to cattle, sheep, pigs and horses.

Comfrey has been used for centuries for its medicinal properties. The Genus name symphytum means heal together and its alternative name is knitbone. The root was pounded and the resulting mucilaginous mash was bound around the fracture or break, the mixture setting like a cast when dry. A tea was traditionally used for colds.

Comfrey has many uses medicinally, the roots and leaves contain Allantoin, a substance that promotes wound healing and tissue regeneration, it also contains Rosmarinic acid which along with the tannins is responsible for the anti inflammatory action.

A poultice of the leaves and or root can be used to heal wounds, burns, bruises, ulcers, dry irritated skin conditions and will help prevent scars. Caution when using comfrey on deep wounds, if the wound needs stitches, it is too deep, the comfrey knits the skin too fast and could trap an infection within the wound.

Always use an anti-septic herb such as Echinacea, calendula or tea tree along with comfrey to disinfect the area to be treated.

It is useful in any kind of inflammatory swelling and reduces inflammation associated with sprains and broken bones.

Because of the presence of pyrrolizidine alkaloids in the comfrey roots, the internal use of root is not recommended. These alkaloids are potential carcinogens and hepatotoxins. Pyrrolizidine alkaloids, are found in the fresh young leaves and in the root, but in two separate investigations were found to be absent in the dried herb.