Improve your vegetable garden by preparing a raised bed for it. According to the University of Illinois Extension, raised beds provide such advantages as better drainage, a longer growing season, easier maintenance and a safe spot to grow invasive plants like mint. Texas A & M University Extension notes that raised beds can help solve problems of poor or overworked soil by essentially building an open-bottom planting container on top of the existing soil, allowing plants to grow in amended soils that are more appropriate for vegetable gardening.
Hammer four stakes at the corners of a 4 foot by 3 foot box with a mallet to mark off the area for the raised bed.
Wrap string around one of the four stakes and stretch it to the next stake. Wrap and stretch the string around each stake to make an outline of the rectangular raised bed.
Dig out the soil in the outlined box to the depth of one shovel head from the surface. Set this soil in a pile to the side of the raised bed construction area.
Mix the soil dug from the raised bed area with 12 cubic feet of landscaping soil.
Break up the soil remaining in the bed, using the shovel, down another 1 foot. Leave this layer of soil in the ground.
Stack concrete blocks on their sides so the holes point up, or arrange landscaping rocks inside the string outline, to make the walls of the raised bed. Use two or more layers of blocks or stones for a final height of 12 to 18 inches. Remove the stakes and string once you set the stones in place.
Scoop the soil mix into the raised bed walls until it fills in the area.
Plant your vegetables in the soil and lay mulch around the plants to lock in moisture and keep the soil warm.