Hey DGC. I wanted to share my way of building a greenhouse that is secure from jackers and the neighborhood kiddos. Use cow panels to build your tunnel. Take two cow panels and attach the ends together with wire. Bend the panels to form a half circle and attach them to your base of the greenhouse. Continue the process to your desired greenhouse length. You can control the height by overlapping the panels to achieve the height that will fit under your plastic. It is an effective way to keep thieves out as well as secure the greenhouse from local kids. It is even strong enough to hold up against strong winds and snow. By the way. That is a Mimosa in the corner on the 4th week of light dep. growing directly in the ground of super soil I have been building for 10 years. Love those microbes!