Liquorice Glycyrrhiza glabra

Liquorice (Glycyrrhiza glabra) is an evergreen perennial herb in the Fabaceae family, native to Mediterranean to central Asia. It grows 1–1.5 m (3.3–4.9 ft) tall and 60 cm–1 m (24 in–3.3 ft) wide, wants full sun and moderate water, and is hardy to about -20 °C (-4 °F). Space plants about 90 cm (35 in) apart.

Plan Liquorice in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.

Liquorice at a glance

Is Liquorice toxic?

• People: moderately toxic
• Cats: mildly toxic
• Dogs: mildly toxic
• Parts: root

Glycyrrhizin in large or daily amounts raises blood pressure and lowers potassium; avoid with heart or kidney disease and in pregnancy.

If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.

Companion planting: what to grow with Liquorice

Good neighbours

• good With Sweet corn: "Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils. Evidence C

Keep apart or take care

• caution With Alliums (onion family): Onions, garlic and leeks are said to stunt beans and peas (allium root exudates may reduce nodulation). Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
• caution With Alliums (onion family): Beans and peas are traditionally kept away from onions, garlic and leeks. Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
• caution With Fennel: Fennel is reported to suppress beans and peas growing next to it. Evidence C

Questions about Liquorice

How far apart should I plant Liquorice?

About 90 cm (35 in) apart, centre to centre. A mature plant spreads 60 cm–1 m (24 in–3.3 ft).

Does Liquorice need full sun?

Full sun: at least 6 hours of direct sun a day.

How much water does Liquorice need?

Moderate water. Drought tolerance is moderate and waterlogging tolerance none.

How cold-hardy is Liquorice?

It tolerates about -20 °C (-4 °F) once established, roughly USDA zone 6.

When does Liquorice flower?

From about June for 4–6 weeks (northern hemisphere; later in cold climates, earlier in warm ones).

Is Liquorice poisonous to cats and dogs?

For cats it is mildly toxic; for dogs mildly toxic; for people moderately toxic. Glycyrrhizin in large or daily amounts raises blood pressure and lowers potassium; avoid with heart or kidney disease and in pregnancy.

What grows well with Liquorice?

"Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils.

Sources and evidence

Evidence grade A (A: strong evidence).

• Plants of the World Online (taxonomy, native range), Royal Botanic Gardens, Kew
• Herbal monographs (European Union herbal monographs and assessment reports), European Medicines Agency, Committee on Herbal Medicinal Products
• Plants For A Future database, PFAF

Notes and assumptions

• Roots run deep and wide; harvest after three or four years. Grown commercially at Pontefract, Yorkshire, from the 16th century (Pontefract cakes). Dies back in cold winters.

Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.

Related plants

• Bush bean Phaseolus vulgaris
• Garden pea Pisum sativum
• Sweet pea Lathyrus odoratus
• Runner bean Phaseolus coccineus
• Broad bean (fava) Vicia faba
• Lima bean Phaseolus lunatus
• Cowpea (black-eyed pea) Vigna unguiculata
• Yardlong bean Vigna unguiculata subsp. sesquipedalis