Sadly, at around ~$80 for greenhouse plastic, it's going to be Home Depot construction grade for me this year. Having a hard time justifying the $30 expense for wire, plastic, and a row cover as it is, since I'm pretty sure I won't get much return (except maybe some gardening therapy in January).
Have you used the 9 gauge wire? Any opinions on that versus the EMT conduit? Or on layering row cover and plastic ala Coleman?
I was thinking of using the "California system" where the plastic/row cover is fastened all around the edges but split and clipped along a top guide wire. That way I could drop the sides most of the time and just pull them up when it gets cold or a frost threatens.
http://edis.ifas.ufl.edu/cv201