Last week I mentioned how early settlers introduced many of the weeds that cause problems for gardeners. Among them is comfrey.
A herb, comfrey can also be a menace as it spreads rapidly and takes a lot of work to remove. Leave a small bit of root behind and comfrey is back in business, spreading like convolvulus.
So, only grow it where it can be confined. Use a tub or trough sitting above the soil or on concrete and prevent the plants from seeding by removing the flowers.
Over the ages comfrey has been known by many aliases – knitbone, blackwort, bruisewort and boneset. Wort is an old common name for a plant or herb.
A member of the borage and forgetme-not family, comfrey will grow in any soil but prefers to be under trees in the shade.
The chief and most important constituent of comfrey root is mucilage which it contains in great abundance, with 0.6 to 0.8 per cent of allantoin and a little tannin.
The roots have been made into concoctions for taking internally. The leaves have been used externally on sprains, swellings, bruises, severe cuts; as a poultice on boils and abscesses, and applied to inflammation where bones have fractured to reduce swelling and assist in the reunion.
A paste of chopped or ground up fresh comfrey leaves, coconut oil and a few drops of lemon juice has even been applied with success to cancerous squamous cell carcinoma lesions. Apparently it is magic on hemorrhoids and varicose veins as well.
The active ingredient in comfrey is allantoin, which repairs tissue, and reputedly has anti-inflammatory properties.
Comfrey is also said to be a good natural worming remedy and conditioner for chickens.
Only small amounts should be taken internally as the toxic effects of the pyrrolizidine alkaloids in comfrey can lead to liver damage if taken in large amounts or over a long period of time.
As for the gardening benefits, comfrey contains high concentrations of nitrogen and phosphorous equal to that of farm manure which makes it great for use as a compost tea.
The leaves are also high in vitamins B, C and E and beta-carotene. With high levels of potassium it makes an ideal fertiliser for any fruiting plant, which at this time of year means tomatoes, peppers, cucumber, melons, potatoes.
The leaves can be used directly on the garden as mulch or added to your compost or liquid manure barrel.
It is best to harvest the leaves just prior to flowering as this is when the nutrient levels are at their highest.
A plastic rubbish bin with lid is ideal for making brews of liquid compost. Harvest the comfrey leaves, chop them up a bit, add water and a little Mycorrcin or Thatch Buster to help with the fermentation. Animal manure and urine can also be added.
Keep the lid on as it will smell, and keep it down the back of the section.
Problems ring me at 0800 466464 (Palmerston North 3570606) Email email@example.com Web site www.gardenews.co.nz
Comfrey has many benefits as a medicinal herb and as a garden fertiliser, but must be kept contained. Photo: FAIRFAX NZ