Water conserving rock gardens can take many different forms and can be a great way to showcase different or unique plants. There are many plant choices available that tolerate rocky sites. Rock gardens can be designed with shade or sun tolerant plants.
Closely observing natural rocky sites is a great way to get inspiration for ideas on how to design your rock garden.
When selecting plants for the rock garden consider choosing plants with the same sun, water, and soil requirements.
A variety of plant types may be used. Groundcovers can create a cascading or trailing effect. Succulents thrive in hot, dry sites and create interesting textural accents. High elevation wildflowers can create a stunning bloom effect.
Careful rock placement is essential to creating a unique garden. Regular placement of rocks creates a boring effect while random placement can seem too chaotic. Carefully select similar rock material of different sizes and shapes and think about plant placement to create a desired seasonal effect.
Avoid too many plants and too many different plants. Soil should be well drained and amended with organic matter or gravel if needed to improve drainage.
The North American Rock Garden Society has an excellent list of books about suitable plants and design and construction of rock gardens.