Common Name: gunnera
Type: Herbaceous perennial
Family: Gunneraceae
Native Range: Argentina, Chile
Zone: 7 to 9
Height: 5.00 to 6.00 feet
Spread: 5.00 to 6.00 feet
Bloom Time: June to August
Bloom Description: Dull red
Sun: Part shade
Water: Medium to wet
Maintenance: Low
Other: Thorns
Tolerate: Wet Soil
Culture
Best grown in evenly moist to wet, rich, humusy, well-draining soils in part shade. Hardy in USDA Zones 7-9.
Noteworthy Characteristics
Gunnera tinctoria, commonly called giant rhubarb or Chilean rhubarb, is a herbaceous, rhizomatous perennial native to stream banks, forest margins near wetlands, and moist bluffs in Chile and Argentina. It is also grown as an ornamental but has escaped cultivation and is considered invasive in parts of western Europe, the United States, Australia, and New Zealand. Mature plants can reach up to 6' tall with a similar spread. The 3' wide, coarsely lobed leaves have prominent venation and are armed with sharp spines. Tiny, dull red flowers are densely packed on 3' tall inflorescences. The main bloom period occurs in summer, but can vary based on climate. The flowers are followed by small, round, orange-red fruits.
Genus name honors Johan Ernst Gunnerus (1718-1773), Norwegian bishop (at Trondheim) and botanist, the author of Flora Norvegica (1766-1772).
The specific epithet tinctoria is applied to plants with sap or other substance that can be used for dyeing. In the case of this species, the roots are high in tannins and can be used to create a black dye.
The common names of this plant refer to the similarities in the appearance of the foliage to common garden rhubarb, although they are not closely related.
Problems
No major pest or disease problems. This plant has escaped cultivation and is considered invasive in some areas. Check with local laws or planting recommendations before adding this plant to your landscape.
Uses
Large, structural accent for pond or bog garden edges and other moist, semi-shady areas.