How to Build an Octagon Flower Bed

Measure the eight sides of your octagon with a tape measure. The distance of the sides can be any length, but each side should be equal. Place a stake in the ground at the end of each of the lines and the beginning of the next. The finished design will look like a stop sign and you will have eight stakes in the ground. It won't be necessary to measure if you are using a border material that is already sized, such as railroad ties.

Prepare the ground for your flower bed. Remove all weeds, rocks and any objects that may prevent flowers from growing. Rake the area and use a tiller to churn the soil and loosen it for further preparation. This will also help remove undesired materials just beneath the soil. Spread 1 to 2 inches of sand and 3 to 5 inches of top soil over the freshly tilled ground and use a hoe to even it out.

Build the border to your flower bed. This can be made of almost anything, but railroad ties or other lumber are easy to set up and ideal for borders. Dig a hole about 6 inches deep on each of the octagon sides. Seat a railroad tie in each of these holes and pack some of the loose dirt around them for support. The railroad ties will settle into the ground over time and become more solid.