and stomach, as well as nausea, griping, abdominal pain, vomiting, and diarrhea." Though the root of the Chinese rhubarb is a key facet of herbal medicine, its leaves can actually be poisonous if consumed in large amounts due to the oxalic acid content. Patients with "arthritis, kidney problems, inflammatory bowel disease, or intestinal obstruction" should refrain from consumption. Cultivation Ornamental use With its large palmate leaves and tall panicles of pink flowers, Rheum palmatum is a bold statement plant for the temperate garden, that grows up to tall and broad. It is hardy down to . It is propagated by seed in the spring, or by root division in spring or autumn. It grows best in full sunlight in well-drained soil. The following cultivars have gained the Royal Horticultural Society’s Award of Garden Merit:- ’Ace of Hearts’ – compact cultivar to ’Bowles’s Crimson’ ’Hadspen Crimson’ Farming as medicinal herb Since it is the roots and rhizome which serve as this plant's source of medicinal usage, special care is taken in their preparation. When 6–10 years old, the rhizomes of these plants are removed from the ground in the autumn when both its stems and leaves changed to yellow wild. Furthermore, the removal of the lateral rootlets and the crown are removed, leaving only the root. Any debris around the root is cleaned off, the coarse exterior bark removed, and the root cut and divided into cube-like pieces to increase its surface area, thereby decreasing the time needed for drying. References palmatum Plants described in 1759 Taxa named by Carl Linnaeus