Megaherbs belong to a group of herbaceous perennial wildflowers growing in the New Zealand sub-Antarctic islands.
They are characterized by their great size, with huge leaves and very large and often unusually colored flowers, which have evolved as an adaptation to the harsh weather conditions on the islands. Livestock introduced to the islands in the 19th century severely reduced the megaherb population, to such an extent that by the late 20th century the megaherbs were threatened with extinction. Since the removal of the livestock in 1993, the megaherbs have regenerated successfully and dramatically.
The term ‘megaherb’ was first used by James Clark Ross during his 1839-43 Antarctic expedition. Joseph Dalton Hooker, the expedition’s botanist, wrote in the Flora of Lord Auckland and Campbell’s Islands that the megaherbs produced “a floral display second to none outside the tropics”.