Swan Creek Park in Tacoma, WA is the largest community garden that I have seen and I’ve been to many. All of the plots except one (there is always one!) were full of produce and/or flowers. It was an interesting range of plants including tomatoes, squash on a lattice frame, corn, peppers and flowers. The entire garden is protected by a black chain-link fence and I had the sense that the gardeners would not suffer fools gladly.
There was also an environmental art show going on and had I more time, there would be more photos of that.