Atriplex are C-plants, with a characteristic leaf anatomy (kranz anatomy). The genus "Atriplex" is distributed nearly worldwide from subtropical to temperate and to subarctic regions. Most species-rich are Australia, North America, South America and Eurasia. Many species are halophytes and are adapted to dry environments with salty soils. The genus evolved in Middle Miocene, the C-photosynthesis pathway developed about 14.1-10.9 million years ago, when the climate became increasingly dry. The genus diversified rapidly and spread over the continents. The C"Atriplex" colonized North America probably from Eurasia during the Middle/Late Miocene, about 9.8-8.8 million years ago, and later spread to South America.
Hardiness (plants) (i.e. precipitation, temperature, and humidity based) and less dependent on the yearly minimum. In contrast the United Kingdom (UK) and Western Europe have an oceanic climate, and experience a narrower range of temperatures that is tempered by the presence of the Gulf Stream. This results in areas like western Scotland experiencing relatively mild winter conditions that enable the growing of subtropical plants, despite being well to the north of subtropical climate areas. The Royal Horticultural Society has published a set of hardiness ratings applicable to the UK. The ratings range from H1a to H7. H1a, higher than , applies to