Comfrey

 

Comfrey is a medicinal, edible plant that comes in a few different forms.  The "common" comfrey has a tendency to spread, both by seeds and rhizomes, and can become a weed in the garden.  "Dwarf" comfrey is a miniature cultivar that spreads mostly by the roots, and is less aggressive about taking over garden beds; it's a favorite for growing dense, weed-suppressing mats around fruit trees and berry bushes.

Russian comfrey, also sometimes called Bocking (after the village in England where the original domesicated cultivars were bred), is a hybrid of the Russian variety, Symphytum asperum, and the European variety, Symphytum officinalis.  As hybrids of two separate types, the Bocking cultivars are vigorous growers.  They are also sterile!  They cannot become invasive, or turn into weeds in the garden.  They also put all of that extra energy into growing bigger, more nutrient-dense leaves, instead of producing seeds.

Since the primary permacultural reason for growing comfrey centers on its use as a mulch-creating fertility pump, Russian comfrey (Bocking number 4) is ideal for homestead growers.  Comfrey has deep roots that mine nutrients from deep in the soil, even in heavy clay like ours in Virginia.  When you harvest the leaves of the comfrey plant and use them as mulch around your fruit trees, berry bushes, rose bushes, herbs, etc, the leaves quickly break down and provide those minerals in a plant-accessible form.  Chemically, the leaves are about 17% Nitrogen, but in a stable form that will not wash away with the first rainstorm like store-bought nitrogen fertilizers. In terms of carbon-to-nitrogen ratio, Russian comfrey leaves are about equivalent to chicken manure.  In other words, comfrey is an organic fertilizer generator.  The soil under these decomposing leaves turns a rich black, and remains moist, a perfect habitat for earthworms and microbes that help your plants absorb nutrients.

The comfrey plants themselves are beautiful fountains of leaves, with arching stems of blue or purple flowers that hummingbirds and various pollinators visit throughout spring and summer.  In winter, these leaves provide habitat for beneficial garden insects and spiders to survive, so that your predatory insects get a head start on protecting your garden from pests in spring.

Comfrey is hardy and long-lived, and with good soil, water and sunlight, it can be fully harvested three or more times in a summer.  That is, you can chop off all of the leaves and spread them as mulch, or add them for a big nitrogen boost to your compost.  Alternatively, you can pick as needed from the leaf fountain, and continuously harvest all through the growing season, gathering about a third of the mature leaves from each individual plant at a time.  Either way, a full-grown Russian comfrey plant generates a remarkable quantity of "biomass," perfect for a home gardener who wishes to avoid purchasing fertilizer or importing mulches from off-site.  In essence, the comfrey plant is a solar-powered mineral pump that helps you build resilience and self-sufficiency into your organic garden.

Medicinal Value

Common comfrey was traditionally used as a wound poultice and healing salve for external injuries, including bruising.  Today, we know that this was thanks to its high levels of allantoin, which is a keratolytic agent (moisturizing and skin-softening chemical) that helps skin slough off dead cells and generate new, healthy tissue.  Allantoins are present in many modern skin creams and healing ointments for scars, dermatitis and eczema, helping to treat dry, itchy, scaly or painful skin.

Aside from its proven use for skin irritations, comfrey is also a very successful binder for cellular tissues.  In fact, care must be taken to not use comfrey on deep wounds, since comfrey can quite literally glue the wound closed too soon, before the inner injury has a chance to heal.  Since wounds must be allowed to heal from the inside out (closing the surface too soon can increase chances of infection), it is not recommended to use comfrey on deep wounds until most of the injury has closed at its proper pace.  However, comfrey is excellent for shallow cuts and abrasions, as well as for treating scar tissue.

Sources conflict on the internal use of comfrey, which is a very nutritious leaf and makes excellent fodder for livestock.  It has been eaten as salads for millennia, and if taken in moderation, is a great source of vegetable protein, vitamins C, B-12 and provitamin A, potassium, calcium, phosphorous, iron and iodine.  However, excessive intake (especially using comfrey regularly as a tea, a supplement, or most dangerously, an extract) can cause liver toxicity.  Because of the severe consequences of that risk, it is not recommended to consume comfrey often, nor in large quantities, and never to ingest the extract or essential oil.

Externally, comfrey is a wonderful tool in the category of resilience for a homestead, providing a first-aid poultice and a balm for irritated skin.  Just crush the leaves (mash or macerate with a mortar and pestle, a knife and cutting board, or even, if you prefer, a kitchen blender) and apply the liquid to the scratch, cut or rash.  Helpful in getting poison ivy blisters to heal.

Other Uses

With proven medicinal uses, excellent livestock fodder qualities, and its biomass production, comfrey really doesn't need other justifications to earn a spot in your garden.  However, it is worth noting that some permaculture enthusiasts endorse Russian comfrey as an alternative (or emergency backup) for toilet paper.  When the 2020 global pandemic shutdowns caused a temporary shortage of toilet tissue products, many people realized for the first time just how vital it can be to have a plan, and a ready substitute, should this vital resource be unavailable.  However, off-grid permies had been talking about perennial, renewable alternatives to wood-pulp paper for toilet hygiene for years before the TP shortage, and comfrey is one of the handful of plants they recommend growing for such alternatives.  It produces copious numbers of soft, broad, strong leaves, and keeps growing even in winter in mild climates like zone 7 in Virginia, so one can harvest a supply of "wipes" year-round.  They also point out that the soothing skin-care benefits of the juice can aid in certain conditions, if the leaves are punctured with fingernails first, or lightly crushed, to release the juices.

It is very important, however, to test such uses carefully for each individual, as the hairs of the leaves themselves can prove an irritant to some people.  The juices may be a treatment for irritated skin, but the exterior of the leaves is not.  Anyone with sensitive skin should test their reactivity to comfrey leaf hairs first on the back of the hand, then proceed to the soft skin of the forearm, before risking use anywhere more delicate.  Comfrey leaf is not a good toilet paper substitute for everyone!  For safer alternatives, see our blog posts about mullein and mallow.

Buying Plants

We carry all three varieties of comfrey, but we recommend Russian comfrey for most gardeners.  If you wish to buy root cuttings or young plants, please email us at mosbysfarm@gmail.com and let us know the quantity and type you need.

Safety Note

Be cautious when using any medicinal plants.  All plants are subject to variability in cultivar, age, growing location, soil, climate, stress, fertilization, etc.  Thus, dosage with any herb or medicinal plant is never precise, as it is with isolated chemicals, and caution is required with any supplementation or therapeutic use of plant-derived medicines.  Please consult with a trained professional if relying upon herbal remedies, and always remember to inform your primary care physician if you use plant-based supplements or medicines.  There can be interactions with prescribed medications, as well as allergic reactions.  When first using any medicinal plant, start small and observe caution; be alert for signs of negative reaction and discontinue if side effects arise, until you can discuss your concerns with a trained herbalist.  Natural remedies are still chemicals!  Use common sense and be safe.