Comfrey (lat. Symphytum officinale) is a plant from the borage family (Boranginaceae), and the popular names of this plant are black root, kilnjak, ox tongue, bee kolinca, big consul, opašica and svalnik. More famous representatives from this family are: borage and lungwort.
It is a perennial herbaceous plant with an upright stem. The stem is branched in the upper part, fleshy and hairy and can grow up to 80 cm. The black root is also branched and grows quite deep. When the root is cut, it is white in color and as such easily breaks and cracks.
The dark green leaves are simple and 15-20 cm long. They are quite rough and covered with small hairs. While the upper leaves are sessile, the lower leaves are on the petiole. The purple, yellow or white flowers are bell-shaped and face down, growing from the axils of the upper leaves. They bloom during summer and early autumn. Comfrey produces small and dark nuts, and one plant usually produces 800 – 2,000 of them in a season.
Comfrey grows throughout central Europe in moist places. These can be the banks of rivers, streams and ditches or the edges of forests. Accordingly, in Croatia it is most widespread in the wet areas of Pannonian Croatia, Lika, Gorski kotar and Velebit. It is very easy to accept and once it starts growing in a certain place it is difficult to remove it.
Types of comfrey
In general, it is possible to distinguish two types of comfrey by the color of the flowers during flowering and by the height of the shoots. This is how purple and yellow or white comfrey differ. Of all varieties, producers have recently shown the most interest in Bocking 14 (Croatian: Podloga 14), a cultivar of Russian comfrey.
Other types:
- Prickly Comfrey, Rough Comfrey
- Bulbous Comfrey
- Caucasian Comfrey
- Creeping Comfrey
- White Comfrey
- Crimean comfrey
- Tuberous Comfrey
- Russian Comfrey, Healing Herb, Blackwort, Bruisewort, Wallwort, Gum Plant
Purple comfrey
Purple comfrey is also called ordinary comfrey. It has a very developed thick root. When the root is cut, it is possible to distinguish the dark brown outer part and the light yellow or white inner part. Purple comfrey shoot grows up to 80 cm. The herbaceous stem is hollow and hairy, and the leaves are alternately arranged to better absorb light. The leaves have pointed tips and are rough, and the branched veins on the leaves are easily visible. When in bloom, it produces purple bisexual flowers that grow in the axils of the upper leaves. They bloom during almost the entire growing season, until early autumn.
Yellow comfrey
Yellow comfrey is also called white comfrey. Like purple comfrey, it has a very developed thick and knobby root. The above-ground stem is annual and unbranched and grows up to 50 cm, so it is slightly lower than purple comfrey. The stem is also hollow and hairy, and the leaves are alternately arranged. The leaves are lanceolate and hairy. Flowering begins in April and lasts until August. While purple comfrey produces purple flowers, yellow comfrey produces yellow bisexual and drooping bell-shaped flowers.
Bocking 14
Bocking 14 (Cr. Podloga 14) is a sterile variety and therefore does not produce seeds, which is also its advantage because it does not spread uncontrollably like other varieties. It was discovered in the 1950s, and is propagated by root cuttings. With mature and strongly growing plants, it is possible to work the soil with a spade through the clumps of leaves, about 7-8 cm below the soil surface. In this way, the crown (crown?) is removed, which can then be divided into pieces. The original plant will recover and any remaining pieces can be replanted and a new plant will grow quickly. When choosing a plant for propagation, it is necessary to make sure that the plant is strong and healthy and that it does not show signs of rust or mold.
Cultivation of comfrey
Comfrey is not a very demanding plant to grow because it contains exceptional ingredients that enable its successful growth and development. However, it is necessary to know certain requirements in relation to watering, fertilizing and propagation.
Watering
Comfrey tolerates dry conditions quite well thanks to its strong and branched roots. However, regular watering will help it to grow more, to be stronger and to form an even bigger root. It is important to water comfrey immediately after planting until the young plants begin to grow.
Fertilization
In relation to the cultivation of comfrey, the need for water and watering stands out the most, while fertilization is not necessary for this medicinal plant because it is of such high quality that it serves as fertilizer for other plants. However, as comfrey produces large amounts of leaves during the growing season, it can be supplied with nitrogen. In addition, it can only have positive results from the addition of animal manure that is applied as a blanket to cover the plant. It can be covered with other combinations that contain nitrogen, for example with grass clippings.
Comfrey is excellent for preparing slurry because it contains nutrients (potassium, nitrogen, phosphorus) that many plants need during the flowering and fruiting phase. For example, comfrey leaves contain 2-3 times more potassium than manure. It is enough to collect 1 kg of comfrey leaves and leave them for approximately 2 weeks in 10 l of water in order to carry out the fermentation. It is necessary to mix the preparation every day and cover it with breathable material. After boiling, the liquid should be strained and diluted with water. For watering plants, the optimal ratio is 1:10, and for spraying, i.e. foliar feeding, 1:50. The preparation thus prepared can be used once or twice a month during the flowering and fruiting phase.
Propagation
Comfrey is most often propagated by roots. At the same time, it is enough to stick a piece of root in the desired moist place in the ground and very quickly the plant will give its above-ground parts. It should be borne in mind that comfrey spreads quickly, so it should be planted away from other plants.
Comfrey can also be propagated by seeds. After flowering, the flower produces a kalavac fruit, which contains many seeds. At the same time, one plant can produce from 800 to 2000 seeds during the growing season. These seeds contain elaiosomes, which are appendages on the seeds that are rich in proteins and fats. Because of this, elaiosomes attract ants and they spread them. The ants bring the seeds into the dwellings and eat the ejallosomes there, and the intact seeds germinate.
Ground
Comfrey thrives very well on neutral soils, but more acidic soils suit it, both in the sun and in the shade. The most optimal soil pH value for growing comfrey ranges from 6.0 to 7.0. Before planting, it is good to prepare the soil by thoroughly watering it so that it is moist and, if necessary, by adding manure.
Climate
Comfrey suits a coastal or continental climate and moist and semi-shady edges of forests or meadows with surface or underground water.
Comfrey planting
To plant comfrey, it is necessary to know the time and methods of planting, the requirements in relation to the type of soil and the most favorable temperature.
Planting time
Comfrey is planted in spring or autumn.
Planting from seeds
Comfrey grows in various valleys or cornfields and other cultivated soils, but it can also be grown in “controlled conditions” in the garden.
It is possible to use a damp cloth or paper as a substrate, i.e. a breeding ground. A cloth or paper is placed in a container and moistened, and then plant seeds are placed on such a moist substrate. It is necessary to check and control the humidity every day and add water if necessary. It is recommended to start with this method of planting before the start of the season itself, for example at the end of February. The germination time is relatively long, lasting about a month or longer. When sowing in pots for transplanting, it is necessary to make a hole of 1 cm and it is enough to put 2 or 3 seeds, which are then covered with soil and watered with a little water. When the plants grow approximately 15 cm, they can be transplanted into the garden.
Also, if you decide to plant comfrey in autumn (October) or even later (December), you need to prepare a garden bed and sow no more than 2 – 3 seeds per nest. It is also possible to sow in shallow rows in garden beds, where the depth should be 0.5 – 1 cm and the distance between the seeds 20 – 50 cm.
Root planting
Although comfrey can be grown from seed, the easiest and most common way to plant it is to use root cuttings. In this case, the root is removed and simply planted in the desired place in the garden, where it should be buried to a depth of approximately 2 cm. For planting, you should choose a place that is wetter and not too close to the beds, because comfrey spreads very quickly and is invasive.
Harvest
Comfrey is usually not harvested in the first season because the plant needs to establish itself. Later, the root, flowers and flower stalks can be harvested. The flowering plant is harvested from May to August, and the root is removed in the spring just before flowering, i.e. in March and April or October and November, depending on when we planted the plant. It is important to remove it before a new outbreak occurs.
Drying
The harvested root can be dried. Such a harvested root needs to be cleaned well, cut lengthwise and cut into cubes, and then dried in the sun or artificial heat at approximately 40°C, while maintaining airiness. Such a dried root has medicinal properties. It must not be dried too slowly, the root can become moldy, and then its most precious ingredient, allantoin, is decomposed.
Diseases and pests
The cultivation of comfrey does not require the use of insecticides because there are still no known pests that can harm it.
Use of comfrey
Since comfrey is a plant intended only for external use for the purpose of various medical conditions, below is an overview of its medicinal properties and the health conditions for which it is used.
The parts of comfrey that are extremely medicinal are the leaves and the root, where the root stands out more because it contains a higher concentration of useful ingredients. Some of the active plant compounds found in comfrey root are: allantoin, phenolic acids, mucilages, glycopeptides, aglycones, saponins and pyrrolizidine alkaloids. Of all the above, allantoin stands out the most, which stimulates the growth of cells in bones, subcutaneous tissue and connective tissue.
Precisely because of allantoin, comfrey is used as one of the best medicinal plants for healing wounds, swellings, scratches, cuts, fractures and bleeding. In addition, it is an indispensable remedy for dislocations, sprains, strained tendons and muscles. Comfrey is only used externally and is a highly valued ingredient in various creams, ointments, gels, tinctures and poultices. For example, comfrey compresses can help with psoriasis, ulcers or varicose veins.
It is not recommended to take comfrey orally because it causes various side effects in many people, such as diarrhea, flatulence, changes in circulation. It also contains pyrrolizidine alkaloids, which can be carcinogenic and have a negative effect on the liver. Pregnant and lactating women, children and chronic patients should not take comfrey, and it is generally recommended not to use it for longer than 4-6 weeks. In 2001, the US Food and Drug Administration issued a warning against the oral use of all products containing comfrey.
Interesting things
Comfrey is thought to come from Asia and Europe, and today it is most widespread throughout Central Europe. Because of its medicinal properties, the prevailing belief was that comfrey originated from the Garden of Eden. Also, due to its exceptional regenerative properties, there is a prevailing belief among the people that two fingers can grow into one if they are connected with comfrey and held like that for a while. This only proves the power of tissue regeneration that this plant possesses.
In folk medicine, it was mostly used for the treatment of wounds, especially purulent ones, and for the treatment of bone pain. In some regions, it is also called “root for a broken leg” because it was once used in the form of poultices for faster bone healing.
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