Mediterranean plants do well :-)
Check out CultiDelta http://www.cultidelta.com/ they sell to the public on saturdays.
Also check out the 'Mediterranean gardening society'
Forget pretty much any plant you will find in garden centres, Bauhaus etc. or brought from the UK.
Here are a couple of potos of our garden I took 5 minutes ago, all mediterranian plants and we don't need to wáter even in Summer!

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