Overview
Rheum palmatum is a clump-forming perennial perennial herbaceous in the genus Rheum, part of the Polygonaceae family, with deciduous foliage. It typically grows around 3.0 m tall. Rheum palmatum grows best in full sun, and tolerates loamy and clay soils and neutral pH. Its UK hardiness is rated H6. Suggested uses include ornamental. It is native to China and Vietnam.
About
Rheum palmatum is a tall perennial herbaceous plant in the knotweed family that can reach about 3.0 m. It is native to China and Vietnam and flowers in the UK from June to July. Plant in full sun on loamy or clay soils that remain moist but are well drained. Harmful if eaten; wear gloves and other protective equipment when handling.
Wikipedia contributors, CC BY-SA 4.0 — Rheum palmatum
About the genus
Rheum is a genus of about 60 herbaceous perennial plants in the family Polygonaceae. Species are native to eastern Europe, southern and eastern temperate Asia, with a few reaching into northern tropical Asia. Rheum species are cultivated in Europe, Asia, and North America.
Wikipedia contributors, "Rheum (plant)", CC BY-SA 4.0 — Rheum (plant)
In the garden
Rheum palmatum is a perennial herbaceous species in the Polygonaceae native to China and Vietnam, noted for its size rather than compactness — plants may reach around 3.0 m. In the UK it flowers in June to July and is treated as a late-spring to early-summer structural element in large borders. Choose a site in full sun with a loamy or clay soil that holds moisture without becoming waterlogged; the plant prefers moist but well-drained conditions. In UK terms it carries an H6 rating, meaning it is very hardy and will withstand most British winters; the USDA hardiness band is 6–9 for those comparing zones. Allow room for height when positioning it and avoid placing it where summer drought is likely unless irrigation is available. Because of its height, place Rheum palmatum towards the rear of a mixed herbaceous border or as a specimen where its scale complements perennial and shrub planting. Take care when handling: the species is harmful if eaten, and the advice is to wear gloves and other protective equipment when planting, dividing or carrying out maintenance. Pets are also at risk if they ingest plant material; for further information and contact numbers consult the HTA guide to potentially harmful plants.
Growing conditions
Best soil and position for Rheum
- Sunlight
- Full sun
- Soil type
- Loamy, Clay
- Soil pH
- Neutral
- Soil moisture
- Moist but well-drained
- Aspect
- South-facing
- Exposure
- Sheltered
- UK hardiness
- H6
Plant details
Rheum palmatum size, habit and characteristics
- Plant type
- Perennial herbaceous
- Habit
- Clump-forming perennial
- Foliage
- Deciduous
- Height
- 3.0 m
- Suggested uses
- Ornamental
- Native to
- China, Vietnam
- Toxicity
- Harmful if eaten. Wear gloves and other protective equipment when handling Pets: Harmful if eaten - for further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
Care notes
Pruning and caring for Rheum palmatum
- Cultivation
- Requires moist, well-drained soil; prefers full sun; protect from strong winds; mulch in winter
- Pruning
- Remove dead or damaged leaves in spring; cut back flower stems after blooming
- Propagation
- Division, seed
- Pest resistance
- Generally pest-free
- Disease resistance
- Generally disease-free
Frequently asked questions
How do I grow Rheum palmatum?
Requires moist, well-drained soil; prefers full sun; protect from strong winds; mulch in winter.
Where is the best place to plant Rheum palmatum?
Rheum palmatum prefers full sun. It suits sheltered positions.
What soil does Rheum palmatum need?
Rheum palmatum grows best in loamy and clay soil. It prefers neutral soil. Aim for soil that stays moist but well-drained.
How do I prune Rheum palmatum?
Remove dead or damaged leaves in spring; cut back flower stems after blooming.
How big does Rheum palmatum grow?
Rheum palmatum reaches a height of 3.0 m.
Is Rheum palmatum hardy in the UK?
Rheum palmatum has an RHS hardiness rating of H6, meaning it is very hardy, tolerating -20 to -15°C across most of the UK.
How do I propagate Rheum palmatum?
Division, seed.
Is Rheum palmatum toxic?
Harmful if eaten. Wear gloves and other protective equipment when handling Pets: Harmful if eaten - for further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants.
