Finding a perennial plant that is both useful and beautiful is such a treat. An herb that’s been in use for as long as comfrey—since 400 B.C.—is bound to have multiple uses. It wouldn’t have been continually cultivated for so long otherwise.
Comfrey is in the same family as borage and forget-me-nots. It shares similar-looking white to blue-purple blossoms and leaves covered in rough hairs. Comfrey is versatile, and you probably know it for its use in holistic medicine. Its internal use is a bit controversial, as the U.S. Food and Drug Administration has issued warnings about comfrey’s pyrrolizidine alkaloid content, which can cause liver damage at high doses, but you’ll find herbalists recommending its limited use as a tea as well as in topical applications.
Outside of traditional medicines, comfrey is a useful herb for the farm, too. It grows quickly in plant hardiness zones 3 through 9 and produces leaves from spring through your first freeze, so you have a ready comfrey supply for much of the year. Here’s how you can put its abundant supply to use on your farm.
1. Comfrey Mulch
Comfrey has tuberous roots that travel deep into the soil, accessing nutrients that many other plants’ roots cannot. It pulls these nutrients—including nitrogen, potassium, phosphorus and calcium—into its leaves. As the cut leaves of comfrey decompose, these nutrients remain in the upper levels of the soil, making them more accessible to other plants.
Make It Happen
Cut comfrey leaves throughout the year, and place the whole leaf over your planting bed. Comfrey leaves can grow quite large, and in addition to helping add nutrients to your soil when used as mulch, will help to shade out weed seeds.
Comfrey makes a good chop-and-drop plant. You can cut off leaves throughout the year and mulch around a tree or other plants in the area. The leaves will grow back quickly, but be aware that it’s only the leaves you’re using. Comfrey roots are extremely prolific, and root pieces will take hold and start growing—comfrey is difficult to get rid of once it roots.
2. Comfrey Tea
This isn’t the tea that nourishes you; it’s the tea that nourishes your garden, just like compost tea.
Make It Happen
Cut comfrey leaves from your plants, chop them, and soak them in water for several weeks, until you have a thick, dark liquid. The Permaculture Research Institute recommends diluting your tea with water 12:1 to 15:1 before applying it to your garden. Comfrey tea is especially good for fruiting crops and seed-filling crops, according to the National Center for Appropriate Technology.
3. Compost Activator
All of the nitrogen held in comfrey’s leaves can help jump-start the decomposition process by feeding the microbes in your compost pile.
4. Make It Happen
Add just-cut comfrey leaves to your compost pile when your pile’s carbon-to-nitrogen ratio is too carbon-heavy. Turn the pile to incorporate the comfrey. However, if your compost pile is already nitrogen-heavy, adding a high-nitrogen material like comfrey will only throw off the carbon:nitrogen ratio further and slow the decomposition process.
5. Weed Inhibitor
Planted in a circle, comfrey will keep spreading weeds and grasses from entering.
Make It Happen
Plant comfrey in a perimeter around a tree—at the outer edge of the tree’s circumference or drip line, according to Bastyr University—to prevent grass and weeds from growing around the tree trunk.
Comfrey grows quickly and can grow large—about 3- to 4-feet tall and around—so be sure to plant these in an area where you do not plan to grow other things.
6. Livestock Feed
You wouldn’t think animals would not like to eat comfrey because of the tiny hairs on comfrey leaves, but sheep, pigs and chickens don’t mind. Even rabbits and cattle will eat comfrey when it’s wilted or dried as hay, according to the University of Minnesota Agricultural Experiment Station.
Make It Happen
To feed fresh, cut comfrey leaves from the plant right before feeding. Cattle will also eat fresh comfrey leaves when they’re chopped. To make hay, cut comfrey leaves from the plant and dry for at least three days before storing them. Don’t think of this hay as in hay bales—this isn’t typically a crop you’ll produce in an area as large as a hay field—rather large, dried leaves of forage.
Comfrey has a high moisture content—85 to 90 percent compared to alfalfa’s 75 to 80 percent—so be sure it’s thoroughly dried before storage so it doesn’t mold. Comfrey should be used as part of balanced nutritional plan for animals, not as the sole source of nutrition for any animal.
Before you go and fill your garden with comfrey, realize that it grows quickly and is difficult to get rid of once it establishes. Be judicious in choosing your planting locations, and appreciate comfrey for all it’s worth.