Rheum palmatum or R. palmatum var tanguticum
Herbaceous perennial related to the edible rhubarb. It is primarily used in traditional medicine, and as an ornamental. Known as Da-huang, it is native to China and Tibet and was widely traded along the Silk Road, hence it became known to Europeans as Turkish (or Turkey) Rhubarb as well as Chinese Rhubarb and East Indian Rhubarb.
Of the numerous herbs renowned for their medicinal benefits in early civilizations, Turkish rhubarb remains one of few still used today in both conventional and herbal medicine. The very first accounts are found in ancient Chinese writings, dating back to 2700 B.C. Many more recent medicinal studies have confirmed the laxative, anti-inflammatory, antiviral, anticancer, liver and cholesterol benefits, making this an extremely valuable herbal medicine. More generally it imparts a sense of improved health and wellbeing. Pregnant women should avoid all intake of the plant since it may cause uterine stimulation. All rhubarb leaves are poisonous if consumed in large amounts due to the high oxalic acid content.
Given good growing conditions the roots can be first harvested after a year, however it’s best to wait for 2-3 years. Wash thoroughly, slice, pierce, and hang to dry and cure for at least 6 months. Some sources say that the stems can be used like garden rhubarb, and in fact are superior in flavour and quite tender, however we cannot substantiate that this is the case.
Turkish rhubarb grows much larger than garden rhubarb, producing jointed stalks that reach a height of up to 2.5m with loosely branched clusters of flowers along with the tips that mature to red from their yellow or white blooms. The leaves have an entire margin in the first year and demonstrate the ornamental palmate structure in the second year. Plants prefer part shade to full sun and well-drained soils.
Main photo: https://alchetron.com/Rheum-palmatum
Others: Kahikatea Farm