I should have thought of this last year before my plants burned up in the May/June heat.
I used the old tarp that was covering one of my water tanks. It's not pretty but it was free because I recycled something I was going to throw away. I was able to attach it to the green house and the fence which was very convenient since I didn't have to try to construct some sort of structure. Everything I build on my own gets blown away by the wind, and it's very windy out here. I added a piece of tarp on the west facing fence to shade the plants from the afternoon sun. I was going to buy some of those plastic chain link slats that weave in and out of the links but this works too.
I bought that trash can last weekend and pumped my washing machine water in to it so that I don't have to trudge up the hill with that watering can 3 times a day. With the shade that I added, my plants only need a watering can and a half. No more wilted plants when I come home from work and I don't have to use my precious water. Note to self...round trash can are better for storing water. I thought these rectangular trash cans were cool looking but the water pushes out the sides and the lid won't fit tight. Oh well. I'll remember that next time I'm trash can shopping.