The empty cells have divided to produce new daughter
colonies, leaving only the colorless remains of the
cell wall. The green cells have not yet divided.
Pediastrum reproduces asexually by producing autocolonies. The protoplast of each parent cell gives rise to a biflagellate zoospore for each cell in the parent colony. The zoospores are freed from the parent cell within a vesicle and then arrange themselves into the cellular arrangement for that particular species. The cells then enlarge until they
reach full size. Each cell can generate a daughter autocolony with exactly the same number and arrangement of cells as the parent colony.
Pediastrum reproduces sexually via the fusion of small, biflagellate gametes that are released from the parent cell. The zygotes germinate into zoospores, which turn into thick-walled polyeders that generate the new coenobia. These polyeders can also result from asexual reproduction.