|Gunnera subsp. var.|
The 40-50 species vary enormously in leaf size. Gunnera manicata, native to the Serra do Mar mountains of southeastern Brazil, is perhaps the largest species, with leaves typically 1.5-2 m (5-6 ft) wide, but exceptionally long, up to 3.4 m (11 ft), borne on thick, succulent leaf stalks (petioles) up to 2.5 m (8 ft) long. It germinates best in very moist, but not wet, conditions and temperatures of 22 to 29 °C.
Only slightly smaller is G. masafuerae of the Juan Fernandez Islands off the Chilean coast. They can have leaves up to 2.9 m (9 ft 5 inches) in width on stout leaf stalks 1.5 m (5 ft) long and 11 cm (4.5 in) thick according to Skottsberg. On nearby Isla Más Afuera, G. peltata frequently has an upright trunk to 5.5 m (18 ft) in height by 25–30 cm (10–12 in) thick, bearing leaves up to 2 m (6 ft 4 inches) wide. G. magnifica of the Colombian Andes bears the largest leaf buds of any plant; up to 60 cm (2 ft) long and 40 cm (16 inches) thick. The succulent leaf stalks are up to 2.7 m (8 ft 10 inches) long. The massive inflorescence of small, reddish flowers is up to 2.3 m (7 ft 6 inches) long and weighs about 13 kg. Other giant Gunnera species are found throughout the Neotropics and Hawaii.
Several small species are found in New Zealand, notably G. albocarpa, with leaves only 1–2 cm long, and also in South America, with G. magellanica having leaves 5–9 cm wide on stalks 8–15 cm long.
Commonly known as "giant rhubarb".
|Standard Cyclopedia of Horticulture|
Gunnera (J. Ernst Gunner, 1718-1773, was a Swedish bishop and botanist, and wrote a local flora). Haloragidaceae. Perennial herbs, some of them big- leaved and used for subtropical effects; others small and useful for bogs and rockeries.
The family Haloragidaceae comprises above 100 widely scattered and heterogeneous species in 8 genera. In the northeastern states are the aquatic genera, Proserpinaca, Hippuris, Myriophyllum. These comprise small and mostly inconspicuous water- or bog- plants. In the Australian region are the endemic genera Loudonia and Meionectes; and there remain Serpicula, Gunnera, and Haloragis, with very wide and disjointed distributions. Gunnera has 25 or more known species in S. Afr., Abyssinia, Java, Tasmania, New Zeal., Hawaii and S. Amer. In general appearance the gunneras are wholly unlike our native haloragaceous plants. The lvs. are radical, ovate or orbicular, in certain species gigantic: fls. perfect or rarely imperfect monoecious or polygamous, small, in simple or branched spikes or panicles, often packed on a great cob-like spike; petals 2-3, or none; calyx none, or with 2-3 lobes; stamens 1 or 2 or 3; ovary 1-loculed, bearing 2 filiform styles: fr. a drupe: plant rhizomatous.
Gunneras are striking herbs, and with protection the two first species may be grown even in some of our northern states. These two are amongst the noblest of lawn foliage plants. To produce satisfactory effects, rich moist ground is indispensable. The plants must never suffer for want of water. Exposure to sun is advisable, but they should be sheltered from severe winds, else the leaves will be damaged. Ample winter protection should be provided. A liberal covering of leaves or Utter, held in place by brush or branches, will generally keep them from harm. Apply the covering in December and remove early in spring. Propagate by division. Seeds are also employed, and they can usually be secured.
Pests and diseases
- Gunnera albocarpa
- Gunnera arenaria
- Gunnera densiflora
- Gunnera dentata
- Gunnera flavida
- Gunnera hamiltonii
- Gunnera kauaiensis
- Gunnera magellanica
- Gunnera magnifica
- Gunnera manicata
- Gunnera masafuerae
- Gunnera monoica
- Gunnera perpensa
- Gunnera petaloïdea
- Gunnera prorepens
- Gunnera tinctoria
G. brephogea. Lind. & Andre. A large species: lvs. tall-petiolate, the limb peltate, concave, orbicuhir-reniform. rather shallowly 7-9-lqbed and the lobes again somewhat lobed or angled, the margin with many small acute inflexed teeth and black-purple: female fla. in a lax spike-like panicle, on a purplish scape. Colombia. I.H. 19:111.—O. minima, Hort.=G. magellanica (?).—G. perpensa, Linn. Lvs. long-petioled (12-18 in.), orbicular-reniform, cordate at base, 0-12 in. across, uniformly and closely crenate-toothed: scape surpassing the lvs., becoming 2-3 ft. high; fls. monoecious, the males in the upper part of the slender spikes. S. ASr. in moist places.CH