Raised bed gardens are constructed so that soil in the garden is raised slightly from the rest of the soil surrounding it. Building a raised bed garden, according to Ohio State University, increases the yield, improves soil conditions, extends the year's growing period and makes your garden easier to work. Raised beds are narrow enough to work from the sides, preventing compaction of the ground by walking on it. Constructing a raised bed need no more than a little extra soil, a tiller and organic material to improve the soil structure.
Select an area that gets plenty of sunlight and is protected from winds, according to Texas A&M University.
Mark off the size of the bed with markers, keeping the bed 3 to 4 feet wide so that it is possible to work on both sides suggests the University of Missouri Extension program.
Dig down one spade's depth and remove the soil from the area, placing it to the side on a tarp. Till the area underneath to improve drainage and root penetration of plants.
Add the soil back to the hole that you previously removed and add a 3- to 4-inch layer of compost on top, the University of Missouri Extension service recommends. Till the organic material into the raised bed and add extra soil so the garden bed is raised slightly.