Common Name: Licorice (American spelling), Liquorice (British spelling), 甘草 (gāncǎo)
Scientific Name: Glycyrrhiza species
Family: Fabaceae (the Legume, Pea, or Bean family)
- Russian/Roman/Eastern European/Hungarian Licorice (Glycyrrhiza echinata)
- Common Licorice (Glycyrrhiza glabra)
- American Licorice (Glycyrrhiza lepidota)
- Chinese Licorice (Glycyrrhiza uralensis)
Licorice is found on all continents but Antarctica, and has been used by humans for thousands of years as a medicine and flavoring. For Permaculturists, Licorice has many other benefits: it is a nitrogen fixer, it is a dynamic accumulator, it provides food and shelter for beneficial insects and wildlife, helps control erosion, and more. It is a multi-use plant and perfect for Forest Gardens and Permaculture projects.
- Licorice has a long history with humans. There was even some dried licorice roots found in King Tut’s tomb dating 3,000 years ago!
- The genus name, Glycyrrhiza, comes from the Greek glykys (“sweet”) and rhiza (“root”).
- Licorice root contains glycyrrhizin (aka glycyrrhizic acid), a chemical which is 30-50 times the sweetness of plain white table sugar (sucrose).
- Common Licorice (Glycyrrhiza glabra) is the species commercially grown today, and it is mostly grown in Greece, Turkey, other parts of the Middle East, and Asia.
- Over 60% of licorice produced in the world goes into tobacco products. Licorice provides sweetness and mellows the other harsh flavors, but does not give a licorice flavor.
- Many “licorice” candies and sweets contain very little real licorice, but are flavored with anise oil instead.
- The first licorice candy was probably made in the town of Pontefract, West Yorkshire, England in 1750 by George Dunhill, in a local apothecary. Sugar was mixed with licorice to make Pontefract Cakes over 400 years ago! Licorice was originally brought to the area by returning Crusaders in 1090 and was eventually grown by Spanish monks at the Pontefract Priory. The root was nicknamed “Spanish” because of this.
- Red Licorice does not come from the Licorice plant at all and do not have anything like a true licorice flavor. They are usually cherry, strawberry, or other fruit flavors.
USING THIS PLANT
- Edible Roots – Can be used raw, but is typically dried. Licorice root is used for flavoring of candies, sweets, and even savory meat dishes, sausages, and alcoholic beverages (most notably beer). The dried roots can also be ground and the powder used. The dried roots can be chewed on, and used to be popular as a tooth cleaner/brush.
- Edible Shoots – Native American tribes would eat the tender Spring shoots raw.
- Tea Plant – The dried roots are a common tea ingredient. It is said to be thirst quenching. The leaves have also been used for tea, mainly for medicine. Typically, only a very small amount is used in an herbal tea, but up to 5 grams are used in one cup of medicinal tea.
- Medicinal Plant – Licorice has been used for centuries as a medicinal (see below).
- Nitrogen Fixing Plant – this plant creates its own nitrogen through a symbiotic relationship with microorganisms (bacteria) in its roots. It typically produces an excess of nitrogen that can be used by neighboring plants. This is a leguminous plant and has several types of inoculants that partner with it.
- Dynamic Accumulator – Phosphorus, Nitrogen. When the herbaceous above-ground portion of this plant dies back each year, it is bound to release the nutrients it has mined with its roots.
- General insect (especially bees) nectar plant
- Shelter plant for beneficial insects
- Lacewings prefer to lay eggs on this plant
- Parasitic Wasps prefer to rest and hide on this plant
- Wildlife Food – foliage (large mammals) and seeds (small mammals and birds)
- There are a number of reports that Licorice can be eaten by livestock. A 1981 study determined that American Licorice is comparable to alfalfa in nutrition.
- Erosion Control Plant – the extensive root system helps stabilize soils prone to erosion
- Pioneer Plant – helps reestablish overused or damaged land
- Licorice has been used medicinally for thousands of years. It has been used in both Eastern and Western traditional medicine.
- Traditionally, it has been used for stomach ulcers, bronchitis, cough, sore throats, and viral or bacterial infections, inflammatory conditions, as well as many, many other ailments and conditions. Herbal medicines are often used for a wide variety of conditions. To me this means that the herbal medicine works for at least some of these problems, or why would it have been used to treat these conditions in the first place? Of course, this is not always true, but it is one of my general rules.
- Licorice root is avaible fresh (if you grow it or harvest it yourself), although most medicinal applications use the dried root.
- Licorice root products, with the glycyrrhizin (aka glycyrrhizic acid) removed is common in modern herbal medicine. These products are called Deglycyrrhizinated Licorce (DGL).
- There have been a number of modern medical studies performed on Licorice, and very little of the traditional medicinal uses for Licorice have been validated. This does not mean Licorice does not work. It means that in these studies they did not work any better than whatever it was they were compared to. What does this mean for us? It means that as long as we are mindful of the potential risks (side effects, medication interactions, and overdoses), Licorice may help with some of our medical problems.
- Heartburn: Medical research shows that Iberogast (aka STW5) can significantly reduce heartburn (aka dyspepsia). Iberogast is a commercial herbal product developed in Germany containing Licorice, peppermint leaf, German chamomile, caraway, lemon balm, clown’s mustard plant, celandine, angelica, and milk thistle. (three times a day for 4 weeks)
- Ulcers: There is some fairly good evidence to show that Licorice may be helpful in treating stomach ulcers.
- Constipation: There is some fairly good evidence to show that Licorice can be used as a laxative. It is considered a stimulant laxative, and it works. Because stimulant laxatives can lower potassium levels, they should not be used for long term or by people with potassium issues or on potassium-altering medications.
- Hepatitis: There is some evidence to show that Licorice may be useful in treating Hepatitis B and C when used intravenously (IV), but these were small studies and most people are not going to self-treat with IV Licorice!
- Other Conditions: There is not enough modern medical research to support other uses, but research has been done on Licorice used to treat eczema (atopic dermatitis), osteoarthritis, cough, viral infections (like the common cold), infertility (specifially polycystic ovary syndrome), lupus, chronic fatigue syndrome, and prostate cancer, as well as to treat the side effects of taking long-term oral steroids. There are a lot of other conditions where traditional medicine practitioners use or prescribe Licorice, and there is a lot of anectdotal evidence to support these uses, so it is hard to verify what really works and what does not. For instance, the tobacco industry uses licorice, in part, because it acts as a bronchodilator which opens the airways making it easier to inhale the smoke (it causes a smoother, easier inhalation… great for smokers, right?!). So, it makes sense that Licorice is used to treat bronchitis, cough, and asthma, but there are no modern studies that “prove” this.
- Problems with using Licorice (this list is not meant to discourage the use of Licorice, but to make sure you are aware):
- Using Licorice in the amounts normally found in food and tea should not be a problem.
- Using Licorice as a medicinal should also not be a problem if not used for more than a few weeks.
- Using Licorice for more than a few weeks, at greater than 30 grams per day, has been shown to cause many medical problems. Remember, if you are using a plant as a medicine, there are potential consequences… both good and bad.
- 5 grams per day may be too much for people with heart disease, high blood pressure, or kidney disease.
- Licorice can raise blood pressure… bad for people with high blood pressure and kidney disease.
- Licorice can cause water retention… bad for people with heart disease or heart failure.
- Licorice can decrease the levels of potassium in the blood. This may cause abnormal/irregular heart rhythms.
- Licorice contains phytoestrogens. These are not the same as hormonal estrogen, but there is some concern that the body may treat them the same. I don’t know if there is great evidence to support this, but there are recommendations to avoid any thing with phytoestrogens in the case of male sexual dysfunction/disinterest, uterine fibroids, endometriosis, or hormone-sensitive cancers (breast, uterine, ovarian).
- For all the reasons listed above, Licorice should be avoided in pregnancy.
- Licorice may interact with some medications, including Warfarin (Coumadin), Digoxin, Furosemide (Lasix), Estrogen supplements (e.g. Premarin), steroids, and many more. If you have a chronic medical condition, especially if you are taking regular medications, then talk to your health care professional first.
- The majority of these problems and interactions resolve themselves after stopping the Licorice.
Yield: Variable. I can only find yield data for large, multi-hectare, monoculture plantings… not that applicable to the vast majority of people.
Harvesting: Roots can be dug from 3-4 year old plants in Autumn or Winter after the leaves have died back. This is a rather labor intensive project. If only the top roots and top parts of the roots are harvested, many of the the deeper roots and root fragments will regrow.
Storage: Licorice can be used fresh or they can be dried. Dried roots will store for well over a year.
DESIGNING WITH THIS PLANT
- Russian Licorice (Glycyrrhiza echinata): Zone 6-10 (some reports say Zone 5)
- Common Licorice (Glycyrrhiza glabra): Zone 8-9 (some reports say Zone 6)
- American Licorice (Glycyrrhiza lepidota): Zone 3-8
- Chinese Licorice (Glycyrrhiza uralensis): Zone 5-9
AHS Heat Zone: No reliable information can be found.
Chill Requirement: Likely considering where this plant originates, but no reliable information is available. As the plant propagates so well via rhizomes, the potential benefit of a chill to increase see production is really not that important.
Plant Type: Medium Herbaceous Plant
Leaf Type: Deciduous
Forest Garden Use: Herbaceous Layer, Underground Layer
Cultivars/Varieties: There are a number of species available, and there are varieties available. It is interesting to note that there are differences in the “wild” Licorice root flavors between different plants. Make sure you have a good-tasting root before you do much propagation with it.
Pollination: Not self-fertile. Pollinated by insects.
Flowering: Summer (June-July)
Life Span: No good information available as we typically harvest the roots, and new plants grow from the remnants or from the rhizomes left over, so an individual’s life span is likely irrelevant.
PHYSICAL CHARACTERISTICS OF THIS PLANT
- Russian Licorice (Glycyrrhiza echinata): 2-3.3 feet (60-100 cm) tall and indefinitely wide
- Common Licorice (Glycyrrhiza glabra): 2-6 feet (60-180 cm) tall and indefinitely wide
- American Licorice (Glycyrrhiza lepidota): 1-3 feet (30-90 cm) tall and indefinitely wide
- Chinese Licorice (Glycyrrhiza uralensis): 1-2 feet (30-60 cm) tall and indefinitely wide
Roots: One or a few deep taproots with rhizomes (horizontal stolons) – these are underground stems that put out new roots and shoots to develop new plants. One report states that Licorice roots can grow to 4 feet (120 cm) in length.
Growth Rate: Fast
GROWING CONDITIONS FOR THIS PLANT
Shade: Tolerates partial shade. Russian Licorice tolerates more shade.
Moisture: Perfers moist soils. American Licorice can tolerate more dry conditions once established.
pH: 6.1-7.8 (prefers fairly neutral to slightly alkaline soils)
Special Considerations for Growing:
- I have found many sources that state Licorice does not like clay and prefers sandy soils. This makes sense considering its origins. Take this into consideration when choosing a location.
- If the location is too cold, the plant may not flower. It can still grow well without flowering.
- The roots do not grow much for their first 2 years. It is really in the 3rd year that the roots get thick enough to harvest. After the 4th year, the roots get tough and fibrous.
Can be propagated by seed. Scarification is recommended, and this is commonly accomplished by soaking in warm water for 24 hours, but can also be nicked with a file. Can also be propagated via Spring or Autumn division. Licorice will propagate well from root fragments as long as there is at least one bud.
Minimal. May need to cut it back if it is growing in an undesired direction… but this should be considered before planting.
Considering that Licorice can grow back from root fragments, has deep roots, and has rhizomes, it can be considered difficult to control and difficult to eradicate once established. This is why thoughtful design is needed before implementation. Personally, I like nitrogen-fixing plants that have many uses and are hard to kill… especially ones that don’t have thorns!
Subscribe to TCPermaculture.com and receive updates whenever a new article is posted!