This information was passed on by Lynne Fish after the Household Waste session on 12th March.
Grassroots Recycling, Old Dairy, North Farm, Warminster. BA12 0EP will take plastic pots and trays which must be free of soil. Lynne thinks they can accept pots there any time they are open but hopefully in large quantities to make it worth the trip. Perhaps someone local works near there or visits?
Another option is to return pots to the Country Market in the Town Hall