The home of the cacti was originally limited to the American continent. Only after the discovery of America did the cacti spread worldwide. Today, for example, the opuntia have become indispensable in the Mediterranean countries.
In Australia and parts of Africa, they became a real nuisance due to the lack of natural regulators. Everywhere in the world where they also grow “wild” outside of America today, they were originally naturalized by human hands. In America they inhabit a wide variety of habitats, from the southern tip of South America, from the coastal strip to 5,000 meters in the Andes, in the north to the Peace River in Canada and in the rocky deserts of the Rocky Mountains.
But the greatest density of cacti can be found in Mexico, the southern states of the USA and around the southern tropic, in northern Chile, Peru and Bolivia.
In their homeland there is a pronounced seasonal alternation between rainy seasons and dry seasons, but one thing has to be clear: cacti also need water. In the absolute desert regions of the world, such as the Sahara, cacti have no chance of survival.
There are some cacti in South America on the slopes of the Andes that manage completely without rain, but they get the moisture they need through condensation from the fog that occurs every day.
I don't want to go into such extraordinary cacti here, because it takes a lot of effort and expertise to take care of such cacti. If you want to get a rough impression of how difficult it is to reproduce the foggy desert climate required for maintenance, you should visit the Palmengarten in Frankfurt, Germany. A fog desert has been set up there.
But let's take a closer look at the cactus locations in the south of the USA, in Mexico, the Andean region of Bolivia and the locations in Brazil and Argentina.
Where do Cactuses Grow?
USA / Arizona
The semi-desert climate here is characterized by very different levels of precipitation. This landscape became famous for the gigantic cacti of the genus Carnegiea gigantea. This cactus, also known as Saguaro, forms columns up to 18 meters high and is world famous for its western backdrop. The cacti are protected from human destruction in the specially established national parks, such as the “Organ Pipe Cactus National Monument”.
But the ferocacti, up to 2 meters in size, and the very stubborn opuntia also catch the eye and shape the landscape. In addition, the small echinocere species that are interesting for collectors are also at home here. They often form large, connected groups and are a splendid sight, especially when they are in bloom.
This is where the popular mammillaria (Pincushion Cactus) and astrophytum (Bishop's Cap Cactus) come from. But Opuntia microdasys (Bunny Ear Cactus) is also at home here. In the north of the country, the climate is particularly suitable for smaller cacti, as rainfalls are very irregular here in summer and do not occur at all in winter. The cacti grow between piles of rubble and under thorn bushes. You have to look closely to discover them.
The south of Mexico is also populated by larger species of cacti, such as the various species of cereus (columnar cacti) and echinocacti. The landscape here is very varied. In the mountain ranges and plateaus, fir and oak forests, the biodiversity is particularly high. Frost is no longer to be expected in these latitudes.
The Andean region of Bolivia
Here in the open and desert-like highlands of Bolivia the small ball cacti such as Echinopsis (Hedgehog Cactus), Lobivia, Parodia, Rebutia and Sulcorebutia occur. These species tolerate the large temperature differences that occur here between day and night. The regularly occurring frosts cannot harm them.
Here the rainfall is already more abundant and the species that occur, such as Notocactus, Gymnocalycium, Frailea and Echinopsis, which grow here on stone and sand hills and between rock and grass, are said to have a higher need for moisture.
The species that grow here, such as Gymnocalycium and Echinopsis, also have a relatively large amount of moisture available. Here on the edge of the pampas, the grasslands of Argentina and Uruguay, they grow in the penumbra between the grasses and bushes.
Peru / Chile
Here you will find extremely hostile areas where it only rains once every 5-9 years, such as the Atacama Desert (El Nino – The weather phenomenon here turns everything upside down). Specialists among the cacti, species such as Capiapoa, Espostoa and Neoporteria grow here. The coastal fog every morning is characteristic, from the moisture of which the cacti draw the water they need.