Comfrey is the common name for plants in the genus Symphytum, which are considered important herbs for use in organic gardening. It’s grown in parts of Europe, Asia and North America, producing clusters of blue, purple and white flowers. It may best be known, however, for its slender, long leaves and black-skinned roots.

The root and leaves of the plant have been used in traditional medicine for many years in areas around the world. For example, in Japan, it was a traditional treatment referred to as “knitbone,” and harvested for more than 2,000 years to help ease joint inflammation and to heal burns, bruises and muscle sprains. Europeans have long used it for treating inflammatory conditions like arthritis and gout. One of the reasons it’s likely to be so effective is that it contains chemical compounds known as allantoin and rosmarinic acid. Rosmarinic acid helps to soothe pain and reduce inflammation, while allantoin helps boost the growth of new cells.

People still use comfrey as a medicinal remedy today, and it’s also quite useful for maintaining permaculture systems.

Something important to keep in mind, however, is that comfrey is toxic to the liver for humans as well as livestock, which means it should never be taken orally or used on open wounds. Some have recommended it as a livestock feed supplement, but for obvious reasons, that’s a very bad idea. It was previously used in its tea form to help treat stomach issues like diarrhea and ulcers, as well as menstrual cramps, persistent coughs, chest pain and even cancer – but experts raised the red flag on it, stating that it contains toxic substances known as pyrrolizidine alkaloids, or PAs, which damage the liver and can lead to fatality. A number of countries, including the U.S., have banned the sale of comfrey-containing oral products.

Still, comfrey offers many other uses, both topically and in the garden. It is very easy to grow, and because the foliage is at its best if cut before blooming time, you don’t even have to wait for the flowers to harvest it. It reaches heights of over two feet and spreads to more than a yard across, but as it doesn’t throw out creeping roots and hardly ever sets seed, it’s remarkably non-invasive.

How To Grow Comfrey

One of the best ways to take advantage of comfrey’s benefits, which we’ll discuss more in-depth a bit later, is to grow it yourself. It can be planted spring, summer or fall – anytime the soil can be worked, and in the warm, southern regions of the U.S. it can be planted and harvested year-round. All you really have to do is grow it, sit back awhile and then reap the rewards.

While comfrey prefers a soil with a pH of 6.0 to 7.0 and does best in rich, moist soil in full sun, it will tolerate some shade and can be grown virtually anywhere, wet or dry. It tends to adapt quite well to just about any environment, and will even thrive in drought where most other plants would wither and die.

When starting multiple comfrey plants, it’s more common to use root cuttings. These are 2- to  6-inch lengths of root which are planted horizontally 2- to 8-inches deep. If you have more sandy soil, plant it deeper. For clay shallow, stick to the shallow end. Space them in a grade, about three feet apart.

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