The Mediterranean area par excellence is, of course, the Mediterranean basin, which is formed by the lands that surround the Mediterranean Sea. This area stretches across European, Asian and African territory, occupying a total area of 2,300,000 square kilometers. It contains some 25,000 known species, of which 50% are endemic. Mediterranean flora presents numerous solutions to adapt to the ecological factors that have influenced its evolution: tough, persistent leaves to withstand the summer drought; thorns, prickles, and toxic substances to defend against herbivores; low plants in the form of cushions or bushes that lose their leaves in the summer to reduce transpiration and so on.
In the Garden, the flora of the vast Mediterranean basin is distributed into four bio-geographic sub-regions: Eastern Mediterranean (between Italy and the Caucasus); Western Mediterranean (the Iberian Peninsula and the Balearic and Tyrrhenian Islands); North Africa (from Morocco to Tunisia); and the Canary Islands.