In 1992, the Desertas were classified as a Biogenetic Reserve by the European Council, in recognition of the high degree of biodiversity and scientific importance of the island's flora. The vegetation is scanty, herbaceous and shrubby, and essentially xerophytic, as revealed by the list of plants that dominate the habitats.
On these islands we find the Smooth Spear-Leaved Spurge (Euphorbia piscatoria), the Pride of Madeira (Echium nervosum), the beautiful purplish-violet flowers of the endemic Madeira Sea-stock (Matthiola maderensis), the Golden Musschia (Musschia aurea) and the Marigold (Calendula maderensis), which adorn the rocky cliffs and arid landscapes of Desertas.
Some endemic species of Macaronesia, such as the Thick-Leaved Groundsel (Senecio incrassatus) and the Bird's Foot Trefoil (Lotus glaucus var. glaucus) are also commonplace on these islands.

DESERTA GRANDE
The rocky cliffs of this island are home to the only endemic species that is exclusive to this small archipelago. The (Sinapidendron sempervivifolium) is a small bush of the family Brassicaceae with fleshy leaves and yellow flowers. The endemic Carrot Tree (Monizia edulis) can also be found on this island.

BUGIO
Though the vegetation here is very sparse, the presence of Blood-eyed Chrysanthemums (Argyranthemum haematomma) is noteworthy, being an endemic species whose flowers have purple disks when young.

ILHÉU CHÃO
The vegetation on this island has been well preserved and includes some of the endemic species found in Madeira, such as (Beta patula) and (Phalaris maderensis).