What Are Some Easy Low Growing Flowers That Do Well in Southern California? Best Answer Will Be Given?

We are looking for some flowers to plant that will stay low (6-12"). The area gets some shade and some sun throughout the day and can be fed by the drip system. Low maintenance and low growing is most important. Please help. We are completely clueless and so are the people at our Home Depot… Thanks.
It would be great if we could plant them just once… I think they are called perennials.

Related posts

• Tomato Plants Not Growing Very Fast, Flowers Just Go Brown With No Fruit Produced, What Is Going On? (7)
• Tips on Growing Flowers From Seed? (3)
• In Growing Flowers, What's the Difference Between "Bright Light" Is Ideal but Avoid "Direct Sun"? (2)
• Does It Work to Grow Flowers in Half-Barrels or Tubs? (4)
• Any Ideas for Landscaping a Shaded Slope in My Front Yard? (3)