The patagonian steppe's aridity is only apparent, as it houses a considerable plant life. After a particularly rainy or snowy winter, the rare and spectacular spring flowering of the desert can be seen: the delicate calceolaria and the lusciously scented flower of the endemic, rugged mata negra are unique treats.

Wild thyme was widely used in native cooking. Local aboriginals also employed the "calafate" resin as an effective teeth-cleaning agent. Other local species, like "te pampa" are locally used for their medicinal properties.

Italian botanist Carlos Spegazzini, a pioneering scientist considered the founder of botany in Argentina, discovered new species of gramineae on a trip to Monte León in 1881.

Some of the most characteristic species to be found at Monte León are:

• Anarthrophyllum rigidum (Mata guanaco)

• Atriplex sagittifolia (Sampa)

• Berberis heterophylla (Calafate)

• Bromus setifolius (Cebadilla)

• Calceolaria sp.

• Chuquiraga aurea (Quilimbay)

• Distichlis sp. (Pasto salado)

• Festuca gracillima (Coirón fueguino)

• Hordeum comosum (Cola de zorro)

• Lephydophyllum cupressiforme (Mata verde)

• Nardophyllum obtusifolium (Mata torcida)

• Nassauvia glomerulosa (Cola piche)

• N. ulicina (Cola piche)

• Poa ligularis (Coirón poa)

• Schinus poligamus (Molle)

• Stipa psylantha (Coirón pluma)

• Stipa speciosa (Coirón amargo ó duro)

• Verbena tridens (Mata negra)