How to Design a Rectangular Herb Garden

Choose a place for your garden. Take the area's light --- from sunrise to sunset --- into account when you make your selection. It may have full sun all day, morning sun and afternoon shade, or a combination of sun-dappled shade and full sun. While many herbs prefer full sun, some herbs thrive in areas of partial shade.

Mark off the garden's perimeter. Measure one long side and drive a stake into the ground at each end of the measuring tape. Tie a taut length of twine between the stakes. Measure each short side, making sure the measuring tape is perpendicular to the first side. Drive stakes into the ground at the proper points and tie off the remaining sides, ensuring the twine is taut.

Test the pH level of the soil in the bed. Take samples from several areas if the bed is large. William Denne, author of "Herbs," says that most herbs thrive in soil that measures between 5.5 and 7.5 on the pH scale, which is a little closer to acidic than it is to alkaline.

Dig 8-inch square holes every 10 to 15 feet so you can inspect the quality of your soil. If it's dry, you'll need to add moist, organic matter. If it's sticky, like peanut butter, you'll need to provide extra drainage. Remove all large rocks and dig out any layers of clay.

Select a theme for your garden. Herbs have different uses, including culinary, medicinal and ornamental. Many formally planned beds have a single theme, or plants grouped by their uses. For example, you can plant a salad herb garden, an aromatic herb garden, or even a tea garden, from which you can make your own herbal tea blends.

Use your theme to guide your plant choices. An herbal tea garden might contain fennel, lavender, ginger mint, peppermint, lemon balm, rosemary and angelica. A medicinal herb garden could contain foxglove, chives, garlic, chamomile, mint, rue, lungswort and golden rod. Write out a list of your chosen plants, including the light needs, height and spread width of each.

Draw your garden on a piece of graph paper, using two squares to represent 1 foot. Draw each plant into the garden, using enough squares to accommodate spread width. Consider how the height and coloring of each plant will affect how the garden looks. Add ornamental plants to your plan if you have extra space to fill. Traditionally, herb gardens contain more than herb plantings. Boxwood, a short evergreen shrub, is often used as a border plant in more formal herb gardens.