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Comfrey, Nature’s FertilizerMaster Gardener ScoopMay 20, 2015

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Comfrey, Nature’s Fertilizer

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By Felicity Rixmann,

Master Gardener

I recently returned after spending five weeks visiting my daughter, Hilary, in New Zealand. It’s such a lovely place to be, especially in February and March when it’s fall there and the fields, orchards, vineyards and hop gardens are being harvested. I was impressed to see strawberries being grown in troughs at waist height, thus keeping the fruit off the ground, weed free and making it easy to pick—no back-breaking stooping!

Hilary has a lovely garden where she and Bruce grow all the kitchen vegetables as well as oranges, lemons, peaches, apples and pears. Dahlias and roses in the flower beds are prolific.

But the secret seems to be organic gardening! They make their own fertilizer from comfrey. Comfrey is a plant that has very deep roots, often going down 6 feet, and because of this, it draws up nutrients from the soil that other plants cannot reach. The leaves of the comfrey are non-fibrous and easily break down to a black sludge which is very potent and must be diluted before use or it will burn the plants. When harvesting the leaves, they fill a five gallon bucket and place stones on top to weigh them down and then fill the bucket with boiling water. This is left for about 10 days. The liquid is then strained off and stored to be used diluted with about 1 teaspoonful to a gallon of water. The remaining leaves can be added to the compost heap, but must be well mixed with fibrous material, lawn cuttings, dead leaves, etc. or the black sludge will ooze out. Comfrey can be harvested four or five times a year, but care should be taken as the stems and leaves are covered with tiny hairs that can irritate the skin.

There is a lot of information on the internet and WebMD. These days, herbalists don’t recommend it for medicinal use although it’s traditional names, knitbone and boneset, indicate that it was once widely used in the treatment of broken bones, sprains, arthritis, and ulcers. It was also thought to have properties for building teeth and bones in children. It is very poisonous!

However, Hilary’s garden proves that it is a wonderful fertilizer. Or is it just New Zealand?

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