It seems to be working because it was beastly hot out there today, but my plants seemed fine. I bought the materials from Home Depot, and it is portable -- so I can move it where it is needed as the season goes on. A computer consultant I use says that he actually uses this method to keep deer out (his garden is fenced, but they jump the fence.)
Here are the directions I used which I got off the the web by looking up "shade cloth":
Buy yourself some 1/2" or 3/4" PVC pipe. It comes in 10ft lengths at your local home center. Bend those pieces, one at a time into an arch, pushing the ends into the ground on either side of your planting area. My raised beds are 4 feet wide and this arrangement works perfectly.Buy yourself some big binder clips from your local office supply. The biggest ones they have.
While at the home center get a roll of fiberglass replacement window screening. You can use either black or gray. The screening needs to be 4 feet wide.
After your PVC hoops are in place unroll the screening and clip it to the pipe with the clips.
Voila!
You have a shade house.
It's portable, it's reusable and best of all, it's effective.
I used 1/2" pipe called "Flowguard". Make sure you get the flexible kind. I got mine at Home Depot -- $1.67/pc. The screen was more expensive. Must be 4 feet wide. I bought a 25' roll. $16.95/roll. Phier replacement screen. It's vinyl, or nylon -- charcoal color.