Rock gardens tend to be fairly static arrangements, because they rely on low-profile ground covers and succulents to create a landscape in miniature, and these plants respond very little to the wind that brings motion to other landscaping features. To add some movement and excitement to a rock garden, you can incorporate a garden waterfall.
In order to carry this technique out successfully, you need to make your garden waterfall part of the foundational structure of the rock garden. To build the rock garden, begin with a clear area of soil. You will need an ample supply of light, sandy soil and rocks of various sizes. We use a well-drained soil in this project so that any water lost from the garden waterfall does not waterlog the rock garden. Place the garden waterfall in the desired location and use it as one segment of a circle made with your largest rocks. Place the rocks as close together as possible. This will form the base of your rock garden. Fill the circle with soil, lightly moisten it with a garden hose, and walk on it to tamp it down. Add more soil if necessary and repeat the tamping process to make a roughly domed surface. Then add more large stones, facing them so the attractive sides are visible. This will be the main structure of your rock garden.
The next step is to choose and add plants. You will need to select plants that will thrive in well-drained soil. Place them in the areas of exposed soil. The effect you are trying to eventually achieve here is of plants “popping” out of gaps in the stones, but you will be constructing it in reverse. It is much easier to plant the greenery when more soil is exposed and add more stones afterwards to create the illusion, than it is to work around tightly packed stones that are already present. When placing greenery, be sure to put a few specimens directly against the side of the waterfall to help unify it with the rest of the rock garden.
Once the plants are placed, add smaller rocks to fill in the holes. Try to conceal as much soil as possible, and add mosses to cover up whatever is left exposed. As the moss spreads it will enhance the illusion of age. Voilà! Your rock garden with waterfall is complete.