A rock garden, put simply, is a small area of land designed to emphasize rocks. Large and small rocks are incorporated into the landscaping as design elements and accented with small patches of perennials. Japanese zen gardens are a type of rock garden that focuses more heavily on rocks and includes minimal plant elements.
A more accessible variety of rock garden, especially for Kentucky gardeners, is the alpine rock garden or rockery. Alpine rock gardens became popular in Great Britain as travelers to the Alps brought back specimens of hardy low-growing plants from the mountains to cultivate in their own gardens. You can see examples of this type of rock garden in many of the large country houses in Great Britain.
Whether you have a sprawling estate of your own or a more modest backyard, rock gardens are a low-maintenance way to add interest to your outdoor space. They do require some careful planning--you don't want to be making design decisions when you're lugging around thirty-pound boulders!
Planning your rock placement depends on personal taste. You could design your rock garden to have a central focal point of a few tall boulders, or you could design concentric rings. A low hill might suggest terracing. Whatever design calls to you, make sure that when it comes time to assemble your vision, you place your largest rocks first and fill in around them with your smaller rocks and plants.
When it come to plants, choose ones that will thrive in well-drained soil and that have similar watering requirements. They should also be hardy and drought-resistant. Remember: the plants' function is to complement your rocks, not to overpower them, so choose small, low-growing plants. Rock gardens, especially alpine rock gardens, are meant to look natural and asymmetrical; try to plant in groups of three, and don't be afraid to create larger patches of a single plant.
Think a rock garden might be your next backyard DIY? Here's a list of plants to get you started:
Sedum (Fulda Glow, Tasteless, and Lemon Coral are a few of the varieties in our greenhouses)
Creeping phlox