Alcantarea imperialis

Alcantarea imperialis is the most regal and is considered the signature species of this genus. It is one of the giants of the bromeliad family.  This Bromeliad grows to a span of more than 1.5 metres, although it can take up to ten years to get to this size.  The thick flower spike reaches up to 3.5 metres in height, producing hundreds of slightly fragrant creamy white flowers.  The green, slightly ribbed leaves are quite leathery and tough with a distinctive waxy bloom over the surface, giving a bluish colouration from a distance.

This species can withstand relatively cool nights, as it is native to mountains of Teresópolis near Rio de Janeiro at an elevation of about 1,500 metres. There it creates the most spectacular landscape, with near vertical cliffs and rocky outcrops of granite studded with these majestic plants.  Each plant establishes its’ own micro habitat, with the gradual build up of humus, mosses and lichens around the root system providing a store of water and nutrients in addition to the reserves held in the copious leaf bases and vases. On these mountains, they are often found in the same areas as 3 other Alcantarea species, A. nahoumii, A. glaziouana and A. regina. However, each of these species occupies a different part of the ecosystem, with a single mountain occupied on each side, or at different elevations, with a separate species. DNA work is being carried out on these species at present, to more accurately determine how closely related they are to each other.

Alcantarea imperialis in the wild are becoming increasingly endangered.  Initially this was from the destruction of natural areas by encroaching civilisation, resulting in large losses of habitat to fire and clearance. Then huge numbers of plants were destroyed from the misconception that having these plants near civilisation was encouraging diseases such as malaria and dengue fever. Finally as landscapers and gardeners realise that these are dramatic and desirable plants for the garden, tens of thousands of plants are stripped from the wild and sent to the cities, or exported. Worldwide, there has been an explosion of interest in these plants, first popularised by the famous Brazilian landscape architect, Robert Burle-Marx.

This wholesale destruction and stripping of Alcantarea from the wild has an immense impact on the whole ecosystem, as these plants are home to innumerable quantities of small animals, insects, reptiles and amphibians.  In addition, the copious quantities of nectar and pollen, produced over the 5-month flowering period, form important food sources for bees, birds, moths and various insects. In my own garden, far removed from their native environments, I have seen queues of up to 4 European honeybees at a time jostling for position in an individual Brazilian Alcantarea flower.


Fortunately, some nurseries in Brazil are showing the foresight to produce large quantities of Alcantarea imperialis from seed and pups with the result that many hundreds of thousands of these plants are now being produced and exported around the world. These nurseries are a spectacular sight in their own right, with row upon row of these giant plants covering the valleys. Production from seed is becoming very common, as each flower stem can produce between 400-600 flowers, which if all successfully pollinated would produce 80,000 to 200,000 seeds!