This should keep the tree-rats, crows, jays, and 'coons away from my tomatoes.
12' length of 6" remesh with a 1' piece spliced onto the top to bring it to 6' tall. Covered with wired-on chicken wire. A 4' 1X frame with hardware cloth stapled to it for a removable top. A 2X4 ripped in half with holes drilled every 6" with the horizontal wires run through it and bent over allow a couple of latches to be mounted for closure. The whole thing is wired to a T-post in back. Opens like a clam-shell for picking. At the end of the season, all eight lay flat on the ground with the top frames stacked on top.
You could do it smaller, depending on the plant size. I've made'em lift-off too for patio tomatoes.