Lily of the Nile plants, Agapanthus, are very common in the San Francisco Bay area.  Originally from South Africa (one of five Mediterranean climates in the world, like coastal California) they do well here.  They take to rainy winters with moderate temperatures (no freezing) and dry summers with no rain, the weather of coastal California. The plants are large, with a waterfall of green leaves year round and beautiful large clumps of flowers in the spring and summer.  Lily of the Nile flowers comes in shades of white and a beautiful blue purple color.  I love the blue purple ones.

                             

The plants have been popular in California for decades, used extensively in landscaping public spaces and private gardens.  In the late spring and summer, they form rivers and pools of blue.  The masses of blooms remind me of water.