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Rock gardens are a beautiful addition to any back or front yard. But for the person who has limited space and still wants to enjoy a bountiful floral or plant experience, they can prove to be mandatory. Rock gardens are used in many different ways and for many reasons. They can fill in an overly spacious area, provide a wonderful way to grow in perpetually wet areas, provide a showy array of plant life in limited space, be used as a form of retaining wall for a sloped area or simply provide a decorative alternative for landscaping. A rock garden provides a new world for alpines and other small plants, requiring little care if you choose your plants wisely.

Rock gardens should ideally slope at a rate of 1 foot for every 4 to 5 feet of width. It is best to find an area of your yard that is near a rock outcropping for a more natural look. In smaller yards you can provide the outcropping by using the same native rocks you use in your rock garden. Doing this will help you keep the landscaping scaled down to the area you have to work with. To begin your rock garden you should strip the slope of all plants and top soil. If your yard does not have an existing slope you might consider adding soil to the area where you wish to put your rock garden. Be sure to provide proper drainage for the area in either case. To do this you will need to dig trenches that are approximately 18 inches deep and 3 to six feet apart down the face of the slope. The number of trenches you dig should be scaled to the size of the slope. Fill the trenches about half full of stones, brick rubble or large sized gravel and then add a 3 inch layer of small gravel over this. It is best to mix your own soil for your rock garden to insure you have a good growing medium. A mixture of equal parts peat moss, loam and rock chips makes a wonderful start for your plants. After this is mixed top the gravel in the trenches with your soil.

Since building a rock garden takes numerous stones you will want to collect them in a variety of shapes and sizes. Start with stones that are about the size of a grapefruit, but be sure you have some larger boulders that will take at least two people to move. It is best to avoid contrasting colors and textures. When your rock garden is complete all the stones should seem to rise from the same bedrock. If you are in an area where rocks are hard to find you can purchase a variety of native stones from any local gravel pit or in some areas landscape companies.

Start building your rock garden by placing rocks at the center of the base of the slope. Use one of the largest rocks as your corner stone. Dig out enough of the subsoil so that you can seat the rock and then position it with its most attractive face out. Continue to dig out and place two rows of progressively smaller rocks until you have formed a rough L shape. Be sure as you place the rocks that the grain is running in the same general direction and tilt them slightly so any run off water will flow toward the slope. Pack your soil mixture between the rocks and place some on them. It is perfectly fine to almost bury the smaller ones on the ends. Build upward from the base stones working with one row at a time. Set each rock firmly into the slope and then bury them with your soil mixture. When you have finished setting all of your rocks you will need to allow the soil to settle for about ten days and then add more soil as it is needed. When this is finished top with 1\2 inch of rock chips which can be found at most local nurseries or garden supply stores.

There are many different plants that will thrive in a rock garden. Low growing junipers like the Armstrong and many others are the best evergreens to use. Alyssum, candytuft, gazania, pansy, verbena, mesembryanthemum or almost any ground cover will give you delightful color. Roses like the climbing floribundas and other climbers will cascade down the walls adding fragrance. It is wise to select a variety of low growing conifers, ground covers, bulbs and low perennials that will thrive in your climate. If your area has cold winters you will want to use alpines such as drabas, edelweiss and mountain avens. If you live in the desert Southwest you should use stone crops, small, spreading peanut cacti and other such succulents. In the humid south such plants as gesnariads, begonias and ferns will flourish in your rock garden. Along the seashore where you need plants that will tolerate the salt spray use thrift and candytuft. Talk with your local nursery to learn the right plants for your area and be sure to tell them you are looking for plants for a rock garden.

Low shrubs and plants such as sand myrtles or dwarf junipers should be planted at the bases of the larger rocks. Rosettes of sempervivum, bright patches of evergreen candytuft or gentians should be planted in cracks throughout the garden. In fact any clinging stone crop will work well when planted in the cracks. Try to find bright ground covers such as baby’s breath, creeping thyme or thrift to hang over the tops of exposed rocks. No matter what plants you decide to use, try to imagine in your mind the color scheme you will have after they are planted and established. Be sure to water and weed continuously until the plants are doing well on their on. After this, if you have chosen your plants wisely your rock garden will need very little attention. Always be sure that you occasionally weed to keep unwanted visitors from taking over your plants. During dry spell you should always water to be sure your plants are getting plenty to drink.