Comfrey’s many favorable characteristics have made it the new “must grow” in permaculture and regenerative gardens. True comfrey (Symphytum officinalis) has a long history as a medicinal herb and as a useful garden plant. Several other varieties have higher N-P-K content than true comfrey and are currently being used in various ways to nourish plants.
Comfrey’s many favorable characteristics have made it the new “must grow” in permaculture and regenerative gardens. True comfrey (Symphytum officinalis) has a long history as a medicinal herb and as a useful garden plant. Several other varieties have higher N-P-K content than true comfrey and are currently being used in various ways to nourish plants.
Recent research on Bocking 14 Russian Comfrey (Symphytum x uplandicum) shows it to be a fast growing cultivar with large leaves that when placed on the soil can provide many nutrients that plants need. Analytical reports indicate that its nutritional value exceeds that of kelp meal and most homemade compost. All comfreys produce an attractive clump of upright green leaves continually and produce seasonal hairy stalks with clusters of small bell-shaped flowers. The leaves can be harvested several times a year for nutritious bio-mass for the garden as well as to use for healing purposes.
Comfrey is in the Boraginaceae family and is a close relative to the herb borage. Its traditional common name of “knitbone” or “boneset” speaks to comfrey’s longstanding reputation as a healing herb. The genus name Symphytum comes from the Greek words symphis, which means the growing together of bones, and the word phyton, for plant. Records indicate that it was prescribed as early as 50 A.D. to heal broken bones as well as wounds and skin problems. The cell-proliferant, allantoin in comfrey leaves is what seems to stimulate the growth of new skin and bone cells. Simple recipes for making salves, ointments or poultices from comfrey can be found online. Drinking tea made from the mature leaves can also help heal minor skin wounds. If using the leaves internally, use only mature leaves and do so in moderation to avoid ingesting any of the toxic alkaloids that have been found in new leaves. Healing properties are also assigned to the roots but most are external remedies.
In the garden, the flowers attract bees and other pollinators and the deep roots pull nutrients to the surface and power-pack the leaves. Comfrey leaves can add fertility when directly applied to the soil, added to a compost bin or made into a tea for foliar application. The most commonly used species for garden use is the Russian comfrey hybrid Symphytum × uplandicum which is a cross between Symphytum officinale (true comfrey) and Symphytum asperum (rough or hairy comfrey). When you consider all of the benefits comfrey offers, it becomes a highly valuable plant for gardeners with any room to grow it.
Comfrey is native to temperate zones of Europe and Asia where it usually grows in damp, grassy places or locally on the banks of rivers and ditches. True comfrey produces seeds and self-spreads easily making it somewhat invasive. The Russian hybrid, however, is sterile and easier to control. Both can be easily propagated by root division. You may want to divide your plants every few years if they become crowded or too large. Simply slice through the plant with a sharpened spade, remove the roots, cut off most of the leaves and replant the section you have cut off.
You can order both seeds and roots online or get a root division from a friend’s plant. Both sexual (from seed) and asexual (from root cuttings) propagation are usually easy and successful. Once you get a few leaves growing from your new plant you can put it out in the garden. Comfrey grows best in full sun or partial shade. It thrives in moist soils but tolerates a wide range of conditions. The plants can grow to 3 feet tall and spread to 3 feet wide and beyond as the roots spread. Removing the plant is not always permanent as any small root left in the ground will regrow. If you have a small yard or you are worried about comfrey spreading, grow it in large pots.
Depending on the variety, your plant may produce flowers in white, pink, lavender, blue or deep purple. All of them have similar properties though the Russian one mentioned earlier does seem to have larger leaves with more nutrients. If seeds appear after flowering, you probably have a true comfrey rather that one of the sterile hybrids. The plants are easy to work with unless you are irritated by the hairy leaves and stems. It is advised to wear gloves when handling comfrey plants to avoid any reaction.
Comfrey is a hardy plant. It will be fine on its own and may grow larger leaves with an occasional addition of organic fertilizer. Avoid over fertilizing as the resulting succulent growth may attract some of the chewing insects that occasionally feed on comfrey.
Comfrey leaves are mature and ready to harvest when the plant is over two feet tall and/or starts forming flower stalks. You can usually harvest mature leaves three or four times a year as new ones grow back quickly. To harvest, cut the plant off about 2 inches above the ground with a sickle, pruning shears or a sharp knife. Revive your plant post-harvest with a good watering and a new layer of mulch.
Hopefully, knowing the wonderful qualities that comfrey brings to a garden will inspire you to call around and find some to plant.
Diana Duff is a plant adviser, educator and consultant living on an organic farm in Captain Cook.
Gardening Events
Wednesday: “Coffee Moisture Meter Calibration Workshop,” 5-6 p.m. at the UH Cooperative Extension Service office in Kainaliu across from the Aloha Theatre at 79-7381 Mamalahoa Highway. Free. Registration required. Contact Gina at 322-4892 or at ginab@hawaii.edu by Monday to register.
Thursday: “Record Keeping for Ag Professionals,” 8:30-11:30 a.m. at the UH Cooperative Extension Service office in Kainaliu across from the Aloha Theatre at 79-7381 Mamalahoa Highway. Stuart Nakamoto, UH Extension Economist, will introduce record keeping tools for agricultural professionals. Free. Record keeping forms available to those who pre-register by Monday at snakamoto@hawaii.edu or call Stuart at 956-8125.
Friday: “Mealani’s Taste of the Hawaiian Range,” 6-8 p.m. at Hilton Waikoloa Village. Food samples offered by local restaurants from local ranchers and food producers plus agricultural exhibits. Advance tickets $45. Available at Kona Wine Market or online at www.tasteofthehawaiianrange.com. $60 at the door.
Saturday: “Work Day at Amy Greenwell Garden,” 9 a.m.-12:30 p.m. Meet at the Garden Visitor Center across from the Manago Hotel in Captain Cook. Volunteers will be able to help with garden maintenance and are invited to bring a brown bag lunch. Call Peter at 323-3318 for more information.
Farmer Direct Markets
Wednesday: “Hooulu Farmers Market,” 9 a.m.-2 p.m. at Sheraton Kona Resort &Spa at Keauhou Bay
Wednesday: “Sunset Farmers Market,” 2 p.m.-sunset at the north makai corner of the Kmart parking lot.
Saturday: “Keauhou Farmers Market,” 8 a.m.-noon at Keauhou Shopping Center
“Kamuela Farmer’s Market,” 7 a.m.-noon at Pukalani Stables
Sunday: “South Kona Green Market,” 9 a.m.-2 p.m. at Amy Greenwell Garden in Captain Cook
Tuesday through Saturday: “U-Pick greens and produce,” 10 a.m.-4p.m. Tropical Edibles Nursery, Captain Cook.
Plant Advice Lines
Anytime: konamg@ctahr.hawaii.edu
Tuesdays and Thursdays: 9 a.m.-noon at UH-CES in Kainaliu, 322-4892
Monday, Tuesday and Friday: 9 a.m.-noon at UH-CES at Komohana in Hilo, 981-5199 or himga@hawaii.edu