Raised Beds in Landscaping

Drainage

• Gardening in a raised bed can help ensure proper drainage to the plant's root system. In areas with poor drainage or heavy soil, the plant's root system can grow above the troubled soil without fear of becoming waterlogged. Some areas have sandy soil, which drains too quickly and leaves the plant's root system starved for adequate moisture in the summertime heat. A raised bed can help ensure that the plant's root system stays moist but not overly wet. The gardener can also add nutrient-rich soil to the raised flower bed to provide adequate nutrients for the plants.

Maintenance

• A raised bed offers ease of maintenance. The gardener will not have to spend an excessive amount of time kneeling or stooping. A raised bed requires remarkably little stretching to reach all sides of a plant. The gardener can even sit in a chair beside the garden or on the side of the raised bed's structure to cultivate in comfort. The work involved in tilling a raised bed becomes dramatically reduced. Adding additional soil each spring helps increase the bed's fertility. Avoid filling the raised flower bed to the rim with soil because it will also require a 2- to 4-inch layer of mulch across its surface to reduce weed growth, keep the plant's root system cool and help the soil retain water.

Plant Choices

• A raised bed can make gardening in remote locations a reality: a roof top, a balcony, a patio or a deck can become a mini-oasis. A wide variety of plant life will thrive in a raised bed. Consider planting shrubs, small trees, perennials, annuals or vegetables. Determine the raised bed's exposure to sunlight when choosing the best plants. During the spring months, the soil warms up quickly in a raised bed, but in the height of summer it dries out quickly. Difficult plants, such as rose bushes, do well in raised beds because the gardener can adequately control the soil's pH, moisture content and nutritional makeup.

Considerations

• When constructing a raised bed, consider installing a drip irrigation system. Plants grown in a raised bed will require a standard application of a general-purpose fertilizer, such as a 10-10-10. Consider using 1 to 2 lbs. for every 100 square feet of gardening area. Always use nontoxic building material when constructing a raised bed. CCA-treated landscape timbers do contain arsenic as a preservative. The North Carolina State University determined that arsenic does filter into the soil of a raised bed constructed with CCA-treated timbers, but that the level of arsenic that accumulates in the soil poses no threat, despite higher levels of arsenic in the soil located by the timber's sides.