Most California Natives should be planted in Fall and Winter. Planting at other times is made complicated by the fact that native plants, like most plants, needs a fair amount of water to get established. Watering in the warmer months is not healthy for most native plants.
Most of us choose native plants because they conserve on water. Though most native plants do conserve water some are thirsty. So pick and place the right plants wisely. Native plants should be planted together and segregated from plants that need more water or summer water. Grouping plants of similar water needs together and providing isolated irrigation to them is one of the essentials of "Water Wise 101."