Our soils are alkaline (pH above 7) because of the areas low annual rainfall and the lack of organic matter. Alkaline soil can be problematic to some plants because if the soil pH is too high it makes it hard for some plants to take up vital nutrients. By selecting plants that enjoy these soil conditions it a lot less work to keep them happy. A good looking landscape with minimal effort, is much easier to maintain.
Below is a list of plant families that thrive in alkaline soil with little to no pH adjustments. From here you can find a variety that fits your yards needs and personal taste.
Feather Reed grasses
Hydrangeas (though big leaf varieties are pink in alkaline soils)
Butterfly Bush (sterile varieties)
Common Snowball Bush
Red Hot Poker
Black Eyed Susans
Golden Rain Tree
Green Ash (Urbanite is resistant to Ash Bore)