I know that it's called a 'floating row cover' around here, and it's a thin non-woven synthetic that you stake like an awning over the plants...and some garden places have it, some don't -

Lee Valley Hardware (leevalley.com) has it for sure.

honestly? I tend to accept some leaf burn in extremes of temperature - but I also have a 3' wide strip of an old (read worn thin) sheet staked above some stuff that I made the mistake of putting in while it was raining, forgetting that summer showers are usually followed by a baking drought :)