Raised bed gardens are gardening spaces where the soil level in the bed is higher than the surrounding ground. Raised beds are small and a great way to get high impact out of a small space. Raised beds also increase accessibility to those who may be less mobile.

Accommodates Low Mobility

Elevated beds are easier to work in than regular flowerbeds and are usually small enough that they can be worked without actually getting into the bed. In these beds, plants and soil are elevated to a convenient working level, making them easier to tend and enjoy. For those who can’t bend over or must garden from a wheelchair, raised beds are a great way to pursue gardening. In fact, hospitals use raised beds for rehabilitation. Raised beds keep plants organized, and confine soil, dead leaves and other debris.

Designing and Building

Building and designing a raised bed garden takes lots of hard work. But it’s worth it. Just ask the gardeners of the Bountiful Harvest Community Garden or the Brooklyn Community Garden.

Bountiful Harvest Community Garden

Henderson County Master Gardeners built the BHCG in 2008. At first the garden was planted directly into the ground but eventually the garden switched to raised beds. Today there are more than forty raised beds of various heights to accommodate gardeners of all ages.

Building a raised bed garden doesn’t need to take hours of painstaking labor and design. You can simply make a mound of soil to use as a raised bed. Cenent blocks or other heavey blocks or stones can be used to outline a bed. Nails or screws and brackets to hold 2×6″ or 2×8″ wooden boards together to form rectangular beds. You can also purchase off-the-shelf kits from gardening catalogs. Most beds are 4′ wide and 6-12 feet long.

Garden centers sell concrete stackable blocks that hold 2×6″ boards for building raised beds.

To achieve the best color displays, annuals and herbaceous perennials must have good drainage. Begin by deep tilling the native soil beneath each bed to improve soil structure and to assure good drainage.

Use permanent materials to construct the beds. New pressure treated wood is ok to use but avoid old pressure treated wood which contained arsenic. Also avoid creosote treated railroad ties. Natural logs can be used even though they will eventually rot.

Steps to Designing a Raised Bed Garden 1)Measure the garden area 2)Make a sketch showing existing structures and plants 3)Draw in the raised beds, irrigation and other structures 4)Till soil beneath the beds if possible 5)Build beds and fill with native soil; add amendments 6)Choose plants according to light needs of the plants and your gardening goals

Soil Considerations

Add organic matter to the ground beneath the beds to improve soil structure if possible. Then, build the elevated bed six to twelve inches high and add a mix of soil and amendments until the bed is full. A combination of composted organic matter such as animal manure, leaves or grass clippings are frequently used to amend beds. If bagged organic amendments are used, apply one 40-pound bag per 100 square feet of bed area and incorporate it to a 6 to 8-inch depth. Ideally the soil will hold some moisture but not stay saturated.

The gardeners rebuilding the Brooklyn Community Garden are using metal raised beds.

Fertilizers

Some people like to incorporate slow release fertilizers prior to planting. Slow-release fertilizers, such as Osmocote, are excellent for flowerbeds because they give the plants a steady supply of nutrients throughout the growing season. A liquid fertilizer can be applied with irrigation water after planting to provide some immediate nutrients.

Mulch

When the planting is done, apply about three inches of mulch on the soil surface to conserve moisture and prevent weeds. Fine-textured mulches, such as pine straw or pine bark mini-nuggets are preferable because they stay seated better on the bed than coarse-textured mulches. Do not use fresh wood chips but composted ones are fine.

Finally, decorations such as trellises and fences can be permanently installed, too. Build them of durable materials such as pressure-treated pine, redwood, cypress or cedar. A properly built raised bed not only improves accessibility it ensures good drainage and improves the visibility of the garden.