Tuberous comfrey

Symphytum tuberosum

Physical Characteristics

Symphytum tuberosum is a PERENNIAL growing to 0.6 m (2ft) by 0.6 m (2ft in) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 5. It is in flower from May to June, and the seeds ripen from June to July. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and can grow in heavy clay soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Distribution

Europe, including Britain, south and east from Germany to Spain, S.w.Russia and Turkey.

Habitats

Woodland Garden Sunny Edge; Dappled Shade; Shady Edge; Ground Cover;

Edible Uses

Edible Parts: Edible Uses: Coffee When roasted until brown and brittle, and then finely ground, the root is used as a coffee substitute. It has a smoothness that is not found in real coffee[183].

Medicinal Uses

None known

Known Hazards

No reports of toxicity have been seen for this species, but the following reports have been seen for S. officinale. This plant contains small quantities of a toxic alkaloid which can have a cumulative effect upon the liver. Largest concentrations are found in the roots, leaves contain higher quantities of the alkaloid as they grow older and young leaves contain almost none. Most people would have to consume very large quantities of the plant in order to do any harm, though anyone with liver problems should obviously be more cautious. In general, the health-promoting properties of the plant probably far outweigh any possible disbenefits, especially if only the younger leaves are used.