Fall Trout Stocking -- Fall trout stocking occurs in a 2-week period (depending on water temperatures), beginning the last week of September and ending before Columbus Day weekend, a 2-week period. Trout waters underlined on the Trout Stocked Waters lists will be stocked during that period in the fall. Due to the short stocking season, fall stocking activity will not be posted on a weekly basis.
http://www.mass.gov/dfwele/dfw/recreation/fishing/trout/trout_waters_nd.htm
The closest to Dedham for trout will be Houghton's Pond in Blue Hills Reservation.