From http://www.northamptonma.gov/

The Reuse Committee will hold a collection and swap of plant pots, in conjunction with Northampton Education Foundation’s “Save Our Schools” Plant and Garden Market between 9am and 1pm on May 10. The public is invited to bring unwanted rigid garden pots and plant trays. All collected pots and trays will be available to the public free of charge; remaining items will be sent to a regional recycling facility. Six-pack plant containers and other crinkly/non-rigid containers will NOT be accepted.

Sign up for automatic notification of collection and reuse events via the City Website's Notify Me feature (select Public Works), or join the Reuse Committee's notification mailing list by sending a request to reusenorthampton@gmail.com.