Bamboo borderPaul uses big bamboo, known as timber bamboo (figure E), which is relatively easy to find online or at retail stores. It's not cheap, but it lasts a long time, even when it's in contact with the ground.
He digs a trench to establish the new border, digging down to a depth of about eight inches and just slightly wider than the bamboo. A trenching tool makes the job easier, but a shovel works as well.
Then, using a bow saw, Paul cuts the bamboo to various lengths between 12 and 24 inches. The random lengths make the border more interesting, but if you prefer a more uniform look, cut all the pieces evenly.