A modular planting system for roof applications includes a plurality of green roof planter modules each comprising a planter including a bottom wall and a plurality of sidewalls that cooperate with the bottom wall to form an interior space, and a biodegradable insert including a bottom wall and a plurality of sidewalls that cooperate with the bottom wall to form an interior space, wherein the insert is adapted to retain a plant matter in the interior space of the insert, the plurality of sidewalls of the insert extend above the plurality of sidewalls of the planter, and wherein the plurality of sidewalls of the insert are adapted to retain a plant matter that extends above the plurality of sidewalls of the planter.
