What is a mediterranean climate region?

San Luis Obispo Botanical Garden displays and preserves the diverse plant life of mediterranean climate regions of the world which include: the Mediterranean Basin, California, central Chile, the Western Cape Province of South Africa, and parts of Western and South Australia.

Mediterranean climates have a long warm dry summer period when rain is rare or scant. Rain falls during a short mild wet period. Rainfall varies in these areas from 10 to 40 inches. These areas all face oceans on their west, which tend to keep temperatures mild. The mediterranean climate areas, whether in the northern or southern hemisphere, all lie roughly between 30 and 40 degrees latitude.


Only 1% to 2% of the worlds’ land mass has a mediterranean climate. Of this, 60% is in the Mediterranean Basin, 22% in Australia, 10% in California, 5% in Chile, and 3% in South Africa. However, some 40% of the world’s plants are native to mediterranean climate regions, and approximately 3% of the world’s population lives there (from Plant Life in the World’s Mediterranean Climates by Peter Dallman, 1998).

In California the Mediterranean climate is commonly considered to extend from Crescent City in the north to northern Baja California in the south. It reaches from the Pacific Ocean to about 2000 feet altitude in the Sierras.

By exhibiting plants from the five mediterranean regions of the world, the Garden draws on the beauty, variety, and hardiness of plants from around the world that share our rainless summers. Not only do these plants require little water, but they need no fertilizers or pesticides which tend to pollute the surrounding environment. The Garden is an exhibition center for these plants so that people can view them and be inspired to use them in their own landscapes.

For more about the plants we grow at the Garden, visit our What We Grow page.