Glycyrrhiza uralensis Seeds | Licorice
LATIN NAME: Glycyrrhiza uralensis
COMMON NAME: Licorice
Plant Profile
Chinese licorice is a perennial that dies back each winter and rebuilds from a deep, branching rootstock. Stems reach roughly waist high on good ground, and where the soil is loose the plant spreads by stolons, so a single seedling can occupy a wide patch over a few seasons. The root is the organ of interest: pale, tough, faintly sweet-scented when broken, and it can be lifted, trimmed and sold without any processing beyond drying.
The species is a plant of open, sunny grassland and lightly saline ground. It tolerates summer heat, long dry spells and soils that would defeat most legumes, and it is one of the few crops that will grow where irrigation has left salt behind in the topsoil.
Leaves are compound and odd-pinnate, with paired oval leaflets and a single terminal one, all dotted beneath with tiny glands that release the characteristic sweet aroma when crushed. Flowers are typical of the pea family, small and pale violet, held in loose spikes from the leaf axils through the warm months. Each pod holds a few hard, kidney-shaped seeds.
As a legume, the plant partners with root-nodule bacteria and fixes atmospheric nitrogen, which is part of why it thrives on poor steppe soils. Fields of it are also used to stabilise and gradually improve saline-alkali land in the Yellow River basin, where few other crops will hold the surface against wind. Established plants are deep-rooted enough to survive on rainfall alone in most of the native range, and the stolons knit the soil surface against erosion.
Science & Biotechnology
The sweet saponin is built from a simple precursor, beta-amyrin, and the route from there to glycyrrhizin runs through two cytochrome P450 enzymes that were first characterised from this very species. One oxidises beta-amyrin at the eleven position; the second performs a further oxidation at the thirty position, and the resulting intermediate is then glucuronidated. Naming those two enzymes in a plant that grows on the open steppe was a small technical landmark, because it turned a cottage trade in wild roots into a tractable pathway problem.
Wild stands are slow to recover and demand for the root keeps rising, so laboratories have looked for other sources. Hairy root cultures induced with Agrobacterium rhizogenes produce the same saponins and flavonoids in a flask, and cell suspensions offer a route to the flavonoids liquiritin and isoliquiritigenin, which are studied in their own right for effects on pigmentation and inflammation.
Uses & Benefits
Three industries lean on the root. Confectionery uses it for the black stick that most people know; tobacco uses it as a casing and flavour for the leaf; pharmacy uses it as a soothing expectorant in cough preparations. In traditional practice it is also the harmonising ingredient in compound formulas, added to soften stronger herbs. The same saponin that makes the root useful can raise blood pressure and deplete potassium when taken in quantity, which is why deglycyrrhizinated forms exist for long-term use.
Growing from Seed
The crop has two famous relatives and the seed pods tell them apart. European liquorice carries smooth, hairless pods; its Central Asian cousin carries inflated, bladder-like pods; Chinese licorice carries pods densely set with stiff glandular prickles that catch the fingers. That third form is why the pods are sometimes described as burr-like. The official root of commerce recognises all three species, and the prickled pods of this one mark it out in the field without dissection.
The seed coat is impermeable, so sowing it dry and hoping is a waste of a season. Abrade the coat with sandpaper or nick the end away from the scar, then soak the seed in warm water until it swells; scarified seed that has taken up water is ready for the ground. Sow about a centimetre deep in a sandy loam, in full sun, and keep the surface moist but never sodden. Space plants widely, at least half a metre apart, because the roots spread and the stolons roam. Established rows need little water and no feeding in most soils.
Keep this identifying cue in view when comparing young plants: the combination of leaf form, stem habit and root response is more useful than a single feature alone.
Our Take
This is a crop for patient gardeners. The first season is modest; the third is when the root has real weight and the sweet smell shows up when you cut into it. If you want to compare species, grow European liquorice beside it on the same ground and see which suits your soil, then read the same page for the smooth-podded form’s habits. I like the prickled pods of this one for a mixed border with Astragalus membranaceus and Codonopsis pilosula, all three being deep-rooted herbs that ask for sun and drainage and give back a fine texture in return.
Related Reading
More species in the same orbit as Licorice: