If you're referring to the empty lot at 12th and Ellsworth that has been cleaned out and is now functioning as a garden, it was cleaned during the big Philly Spring Cleanup by volunteers from Circle of Hope church and the Passyunk Square Civic Association, as well as other neighbors.

I have the contact information for one of the guys who spearheaded the effort. I'm not sure if he'd want his info spread widely, but if you want to send me a PM I'll give you his email.