When you build a rock garden, you are making a miniature environment. Make sure the stones you choose match the stones in the rest of the garden. Keep the size of your property in perspective also. A tall wall in a small area will only make it look smaller and a small one will get lost and not appreciated in a large one.
Take a good look at the place you choose. You want your rock garden to look as natural as possible. Do you have a natural rock formation on the site? If so, pick rocks that match and make the garden an extension of the natural stones. Make sure the site is getting enough sun. Cut back on shrubs and trees if necessary. Remove any soil that covers the rocks. Working off of natural rock groupings is the easiest way to design a rock garden.
A rock garden is the perfect solution for a hard to landscape sloping yard. It would mean no more lawn mowing at a steep angles.
Most plants that are suitable for rock gardens need full sun. If you get some that need partial shade, plant them in the shadow of taller plants.
Start outlining the garden with large boulders. They are the backbone, the spine, of the garden. Set them and the rest of the into the ground so it looks like they were put there by Mother Nature. After you have the boulders in place, fill in with medium size rocks. Then fill in the spaces with small ones.
The next thing is to get the site ready to receive the plants. Remove any grass and weeds and make sure to get their roots as well. Till the soil to the proper depth. Dig a hole about 6 inches deep and fill it with water. Watch to see how the water drains out. If it is not drained out in 12 hours at the latest, you have a heavy soil.
The plants will need a well-drained soil. If the soil is heavy, add a six-inch layer of gravel or crushed rock. Cover that with two inches of sand then add the soil on top. Add sand to the soil as well.
Amend the soil according to the plants you intend to use. If you are using more than then one type and they need different soil conditions and fertilizer, make sure they are in separate areas where you can give them what you need.
Place a flat layer of gravel or crushed rock that matches the color of the rocks around the edges. This will help keep the grass where it is supposed to be and not in the garden.
Put in an irrigation system if your area is prone to droughts. After you have the plants in, lay down a thin layer of crushed rock to keep the weeds at bay. Hand pick any weeds that do appear. Give them a light layer of pine mulch in the fall for extra protection.
Source: TLC
