Prepared by Bob Polomski, Extension Consumer Horticulturist, and Debbie Shaughnessy, HGIC Horticulture Specialist, Clemson University. (New 03/99.)
Gardeners with steeply sloped or poorly drained sites can improve their sites through the use of raised beds. Create a permanent raised bed with used cross ties, concrete blocks or similar rot-resistant material. Fill this area with a mixture of good topsoil and compost. Narrow beds (about 3 to 4 feet wide) allow the gardener to reach the center of the bed without stepping into the bed.
Raised beds warm up faster in the spring, so the growing season begins earlier. They are easier to take care of, as only the area of production must be weeded, irrigated, mulched and harvested. Raised bed gardening saves space, prevents soil compaction and produces better-quality vegetables.
Carefully plan the layout of the beds. Place the beds in a well-drained site that receives a minimum of six hours of sunlight per day, preferably near a water source. Beds can be as long as desired, but only as wide as can be easily worked from either side. Never walk on beds once they have been constructed. All cultivation, planting and harvesting is done from the path between the beds. Paths should be 1 to 2 feet wide. When the dimensions have been determined, mark out the garden with stakes and string.
Work the beds as deeply as possible. If the soil is compact, wait until it is dry enough to break into small chunks. Work in a 2- to 3-inch layer of organic material such as compost, ground bark, leaves or manures. Adding an additional source of nitrogen will help the organic material break down. A soil test will indicate whether other nutrients are needed.
Shape the bed with a shovel and rake. Shovel the walk area to a depth of six inches. Add the excavated soil to the top of the bed. The finished raised beds should be 4 to 12 inches above the paths. Either mound or enclose the bed. If mounding, rake the soil so the sides slope up at a 45 degree angle. Rake the top of the bed so that it is flat. If beds are enclosed, use insect-and decay-resistant wood such as cypress, redwood or cedar. Once the en-closure is made, rake the soil flat. Add sawdust or bark to the paths between beds to improve the walking area.
Plant vegetables in blocks instead of rows. Interplant crops which mature at different times. Plant successive plantings of the same crop so harvest is spaced over a longer period of time. Fertilize and water as needed. Raised beds will dry out more quickly than flat beds, and will require more irrigation during dry periods. Place stakes at the corners of the beds to prevent the hose from dragging across plants.
Organic material is constantly decomposing, so replenish your raised beds with compost regularly. Cover the beds with 2 inches of leaves, compost or a cover crop like crimson clover or fava beans each autumn or early spring. Turn under cover crop or leaves in spring, and plant again the next year.
Excerpted from the South Carolina Master Gardener Training Manual, EC 678.
Page maintained by: Home & Garden Information Center
This information is supplied with the understanding that no discrimination is intended and no endorsement of brand names or registered trademarks by the Clemson University Cooperative Extension Service is implied, nor is any discrimination intended by the exclusion of products or manufacturers not named. All recommendations are for South Carolina conditions and may not apply to other areas. Use pesticides only according to the directions on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Follow all directions, precautions and restrictions that are listed.