The days of a house surrounded by an enormous lawn and garden the size of a city block are long gone. With homes being built closer together and yards getting smaller, the scale of gardening is shrinking, too. But smaller features and smaller plants can pack just as much punch as the grandest garden. Limited space? Problem slope? Rocky soil? Perfect places for a rock garden!
Unlike a large garden with lots of plants creating masses of color, a rock garden is more interesting up close. "It's a jewel box garden," says Christie Mackison, owner of Shooting Star Nursery in Central Point. With tiny plants displayed like a collector's specimens, you're invited to stop and look more closely. Individual plants can really show off in a rock garden.
Start creating your rock garden by tilling up and amending your soil. Well-drained soil is essential. Kathy Allen, designer and owner of a spectacular rock garden featured in our April issue, uses a mix of equal parts sand, 1/4-inch crushed rock and leaf mold for a fast-draining "scree garden." For a general rock garden soil, she suggests one part topsoil, one part 1/4 or 1/2-inch crushed gravel and one part leaf mold or compost. Push your dirt around to make mounds and curves. Now comes the hard part.
Enlist the aid of friends and proper equipment such as a hand truck or a small garden tractor. If you spend the day muscling rocks around by yourself, you're going to wish you'd opted for a condo. Some of our local landscape suppliers will not only deliver, but will actually place your large boulders where you want them, if they can. Whether purchased or collected, your choices of rocks can be all different sizes, shapes and colors, from moss-covered boulders to river rocks.
"Use large rocks to anchor your mounds," says Mackison, and tall, vertical rocks as backdrops. Don't make the mistake of using sandstone, she warns, or you'll be disappointed when they break down and disintegrate. Bury some of your rocks partway into the ground so they look natural. Gravel paths surround Allen's rock gardens, so she can get up close and personal with small plants.
Plant selection is virtually unlimited. You can collect specimens from far and wide, but many of our most common local compact shrubs and perennials work well in rock gardens, according to Rob Griffiths, manager of Southern Oregon Nursery. Make sure your choices have similar requirements for water and exposure, he suggests. Size is the most important consideration, adds Mackison.
Plant suggestions for a sun rock garden include small lavenders, dwarf conifers, sedums, grasses such as blue fescue, dianthus, thyme and alpine perennial asters. Shade rock gardens can feature ferns, dwarf columbine, some carex grasses, dwarf hostas and hebes. One of Mackison's favorite grasses is Deschampsia 'Northern Lights,' with its beautiful variegated cream-colored and green blades.
Give careful consideration to the placement of the plants, because the rocks can both shade and cool the plants, or they can retain heat on the sunny side, says Griffiths.
A few annuals can be added for color spots, but generally the focus is on small shrubs and perennials, because you don't want to disturb your garden every year replacing annuals, says Mackison.
A rock garden is easy to maintain. Most rock garden plants live on the lean side, so a dose of slow-release fertilizer in spring and some water during hot, dry weather will keep them happy. It's important to keep weeds from taking over, especially around tiny plants. A little trimming here and there should keep things neat and tidy.
Then, lean with your back against a rock and enjoy the jewels of your labor.