Raised flower beds offer several advantages over traditional flower beds. A raised bed no more than 4 feet wide allows you to access all parts of the bed from outside it, which means you will never walk on the soil and compact it. It also simplifies weeding and other maintenance of the bed. Raising the bed 12 inches off the ground makes it more comfortable to work in. Build a raised flower bed with a few boards and some basic tools in no more than an hour.
Cut the redwood 4-by-4 board into four, 1-foot lengths. Save time by asking your home improvement center or lumber yard to cut your board for you; there may be a small charge for this service, although some places will cut them for free.
Cut two of the red cedar 2-by-6 boards in half, creating four, 4-foot-long pieces.
Lay two of the 1-foot, 4-by-4 boards on a flat surface, 8 feet apart. Lay one of the 8-foot red cedar 2-by-6 boards on top of the 4-by-4 boards so the 2-by-6 board lines up with the bottom edge of the 4-by-4 boards and the 4-by-4 boards are positioned at the ends of the 2-by-6 boards. Use three galvanized spiral nails to attach the 2-by-6 to the 4-by-4 boards.
Lay another 2-by-6 board just above the first one so it forms a 12-inch high wall with a 4-by-4 at either end. Attach with the nails.
Repeat Steps 3 and 4 with the remaining two 1-foot 4-by-4 board sections and the two remaining 8-foot red cedar 2-by-6 boards.
Stand one of the sides up and nail one of the 4-foot, 2-by-6 boards to one of the 4-by-4 boards. Stand up the other side and nail the free end of the 4-foot 2-by-6 to the end 4-by-4 board.
Nail one of the 4-foot 2-by-6 boards to the open end of the 4-by-8-foot box that you are creating. Nail the remaining two 4-foot 2-by-6 boards in place to finish off the ends of your box. You now have a 12-inch high, 4-foot wide and 8-foot long box with no top or bottom. This is the frame for your raised bed flower bed.
Place the raised bed box in its final location. Make it accessible from all four sides. Fill the box with a combination of garden soil, loam and organic fertilizer in equal proportions. Do not walk on your flower bed. Do all maintenance from outside of the bed.