A raised garden bed lets you grow many kinds of plants that may not perform well in your regular garden soil. Raised-bed gardening gives you control over weeds, soil nutrition and drainage that may not be possible in the rest of your yard. The location of your raised bed may govern what you grow, but a 4-foot by 6-foot bed lets you choose among vegetables, blooming native perennials, annuals and even fruit.
1. Planning for Planting
One of the great advantages of a raised bed is that it is a manageable space to fill with good growing soil. Line your bed with landscape cloth to reduce intrusive weeds. Dig in abundant organic matter, to provide both good nutrition and good drainage. Read up on the acid-alkaline, or pH, soil preferences of the plants you want to grow, and add lime, sulfur or other soil amendments as needed to create the correct balance. Plant good soil before you plant anything else, and your garden will grow well.
Most annual vegetables grow best in pH-neutral to slightly acid soil, and the majority require full sun. If your raised bed is located where it receives six or more hours of unshaded sunlight a day, you can fill your bed with peppers (Capsicum spp.), varieties of which can be grown in U.S. Department of Agriculture plant hardiness zones 1 through 11, and tomatoes (Lycopersicon esculentum), in USDA zones 2 through 11. For sun-loving vining vegetables, you can extend growing space with a vertical trellis. Cool-weather vegetables like lettuce (Lactuca sativa) do best in partial sun of four to six hours a day, morning sun and afternoon shade, or full-day filtered sun. You may be able to plant as many as three successive, cool-weather crops -- early spring, early summer and late summer for fall harvest, depending on your local frost zones.
3. Annual Cutting Garden
A cutting garden lets you fill your house with flowers without diminishing all the color spots in your overall landscape. An annual garden provides a rapid abundance of color, then lies fallow during winter, maximizing your flower supply while minimizing plant care. Choices range from vivid nasturtiums (Tropaeolum majus), zinnias (Zinnia elegans), and asters (Callistephus chinensis) to frothy snapdragons (Antirrhinum majus), stock (Matthiola spp.) and cosmos (Cosmos spp.). Starting some flowers as seeds and others as seedlings will extend your cutting flower supply from early summer through fall.
4. Perennial Herbs, Vegetables and Flowers
Both edible and flowering perennials simplify caring for a raised-bed garden. Sun-loving Mediterranean herbs like Salem rosemary (Rosmarinus officinalis "Salem") is perennial, winter-hardy in USDA zones 7 through 10. You can devote a raised bed to long-lived perennial edibles like asparagus (Asparagus officinales), hardy in USDA zones 3 through 8, blueberries (Vaccinium spp.), species of which are hardy in zones 5 through 10, and rhubarb (Rhubarb spp., syn Rheum), in zones 3 through 8, for up to 15 years of delicious produce. Native blooming perennials, like coneflower (Echinacea spp.), hardy in USDA zones 3 through 8, and lavender (Lavendula spp.), varieties of which flourish in zones 5 through 10, tolerate local growing conditions, bringing color and often fragrance late spring through fall and attracting insects and wildlife to your yard.