To make a U cover (better description is an n shape) for climbing beans would be quite a job and probably expensive if you don't have the materials around the yard now. We had climbing bean at the Men's Shed over 8' tall. Beans don't need bees. For dwarf beans you could go to Bunnings and buy a roll of wire netting (dog mesh or similar) - I think they do 5 M rolls. 1200mm or 1500 mm high would be better. Make a shape like a small n - 1200 mm 400 up each side and 400 across the top. With the 1500 mm 500 up each side and 500 across the top. Cover with 50 or 70% shade cloth - ($5/mtr Bunnings). Shade cloth is 1800mm wide - so put that over the top and lay some wood posts or what ever along the cloth on the ground - also put a piece of tin or wood on the end to stop them going in that way. My plants are growing pretty good - will be interesting to see if they flower soon. My tunnel is a little small.

- Mike