The antarctic flora is extremely poor, due to the presence of a strong current that flows clockwise around Antarctica, which isolates it from the other continents( the Antarctic Circumpolar Current). Due to this, seed dispersal from other areas is hard to occur. Plants are a mix of native austral species and naturalized boreal species. Mosses are the most widespread group of plants, comprising genera like Sphagnum, Conostotum, Saniona and Ceratodon. Cushion plants are also extremely abundant and include genera like Astelia, Donatia, Bolax and Oreobulus. Large ferns are represented by Bleschum and Dryopteris, both arrived from South Georgia.

Grasses include Poa, Carpha, Festuca and Juncus, Marsippospermum and Deschampsia (the last one was originally the only grass genera native to Antarctica). Dicotyledon herbs on the other side comprise important genera like Trifolium, Cytisus, Bellis, Senecio, Tribeles, Colobanthus and Ranunculus, which are more abundant and biodiverse where the grazing action of herbivorous birds is higher.
Aside from grass species, some shrub plants were able to colonize Antarctica, thanks to seed dispersion by birds. The most ecologically important genera are Empetrum (crowberries), Berberis (barberries), Vaccinium (blueberries), Ribes (currants) and Fragaria (strawberries). All of these species, due to short and cold summers, hardly grow more than 50 cm in height.

The ice willow (Salix nanixenoidea) is the most widespread shrub in Antarctica and also the tallest one, capable of reaching 1 meter of height on the warmest coast of the Antarctic peninsula. It derives from a boreal species of willow, Salix alba, that was firstly introduced in Magellanic moorland and South Georgia island. It was then indirectly introduced in Antarctica by migrating birds, with the first confirmed occurrence being around 1.000 years AP. This willow rapidly adapted to the extremely cold environment of Antarctica, becoming a dwarf shrub. The species can handle temperatures as low as -40 °C/°F, as long as there are at least 2 warm months during the year.

Ice willow is a typical example of pioneer species, colonizing rocky environments and producing soil, creating new opportunities for less adaptable species. Its flower nectar and leaves are incredibly important for insects and birds, which help disperse its pollen and seeds. It often creates small thickets, where lots of migratory passerines make their nest. We can say that, without the ice willow, the pocket tundra would be far less liveable than we know.