How to Build a Rock Garden on a Slope

Rock gardens built on a slope can help prevent soil erosion.

Rock gardens provide rugged durability in a garden that needs almost no attention or maintenance whatsoever to remain attractive. When planted with perennials, the amount of care required to maintain a rock garden falls to almost nothing at all. They make excellent decorative features for sloped terrain as well, where it may be difficult or impossible to mow grass. In addition, minimal excavation is required to get started.

Things You'll Need

• Large boulders and rock
• Perennial plants
• Shovel
• Rototiller
• Stiff-tine rake

Instructions

1. Till the area with the rototiller where the garden is to be located to break up solid ground and make excavation easier. Allow the tiller to work to the deepest depth it can manage.

2. Excavate the area where the boulders and rocks are to be installed using the shovel. To create an aged look, each of the rocks should be half buried. Determine the place for each rock and stone, and dig that spot appropriately. It is best to position the rocks in as natural possible. Nature does not adhere to design theories, so it isn't necessary for you to, either. Place the rocks wherever you think they look best.

3. Insert the rocks and boulders into their respective excavations, then fill the gaps between the rock and the dirt with the excavated dirt. It is easiest to have the boulders and rocks delivered and placed on the uphill side of the slope so that they can be rolled downhill, rather than pushed uphill.

4. Smooth the sloped ground surrounding the rocks with a stiff-tine rake, then plant the area with an assortment of perennial flowers and ground cover plants to retain the soil between the rocks. Because it is on a slope, it is very important to have vigorously-growing, and deeply rooted plants to help retain the soil when it rains. This also helps impart a more natural look to the rock garden, which is the ultimate goal.

Tips & Warnings

• Avoid using design books for ideas for your rock garden. Instead, take a walk in your local parks to see how nature deposits rock formations.

• Boulders and rocks can be extremely heavy and cumbersome to move. Make sure that you have plenty of help when you need it and take frequent work breaks while constructing the rock garden.

References

• "Rock Garden Design and Construction"; North American Rock Garden Society; 2003
• "Garden Stone: Creative Landscaping with Plants and Stone"; Barbara Pleasant; 2004
• "Hillside Landscaping: A Complete Guide to Successful Gardens on Sloping Ground"; Editors of Sunset Books; 2007