Overview
Rheum australe is a perennial herb in the genus Rheum, part of the Polygonaceae family. It typically grows around 3.0 m tall. Rheum australe grows best in full sun, and tolerates loamy and clay soils. Its UK hardiness is rated H7. It is native to Himalayas.
About
Rheum australe is a perennial herb native to the Himalayas that can reach about 3.0 m in height. It flowers in the UK from June to July. Plant it in full sun on loamy or clay soils that remain moist but drain well. Parts are harmful if eaten, so wear gloves and protective equipment when handling.
Wikipedia contributors, CC BY-SA 4.0 — Rheum australe
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 australe (Himalayan rhubarb) is a large perennial herb from the Himalayas that produces its flowers in the UK from June to July. Mature plants reach roughly 3.0 m, giving a strong vertical presence where they are established. Choose a sunny site on loamy or clay soil that stays moist but does not remain waterlogged; good drainage is important even where moisture is retained. The plant is rated H7 for the UK (fully hardy) and corresponds to USDA zones 5–9, so it tolerates the coldest British winters but still prefers reliably damp soil in summer. Give each plant generous space so air can move around the crown and root run is unrestricted. Use Rheum australe at the rear of a large herbaceous border or beside areas that naturally hold moisture, where its height will not be overwhelmed by surrounding planting. Exercise caution around children and animals: plant parts are harmful if eaten, and protective gloves are recommended when cutting or dividing. Allow for its eventual size when siting a specimen, since an individual can approach 3.0 m and occupy a substantial footprint.
Growing conditions
Best soil and position for Rheum
- Sunlight
- Full sun
- Soil type
- Loamy, Clay
- Soil moisture
- Moist but well-drained
- UK hardiness
- H7
Plant details
Rheum australe size, habit and characteristics
- Plant type
- Perennial herb
- Height
- 3.0 m
- Native to
- Himalayas
- 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 australe
- Propagation
- Seed, division
Frequently asked questions
Where is the best place to plant Rheum australe?
Rheum australe prefers full sun.
What soil does Rheum australe need?
Rheum australe grows best in loamy and clay soil. Aim for soil that stays moist but well-drained.
How big does Rheum australe grow?
Rheum australe reaches a height of 3.0 m.
Is Rheum australe hardy in the UK?
Rheum australe has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
How do I propagate Rheum australe?
Seed, division.
Is Rheum australe 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.
