By delaying pollination with flowers of Petunia hybrida for up to 5 days, the viability of aged pollen and the numbers of seeds resulting from crosses declined with aging of either staminate or pistillate parent. In the resulting generation, given enough time to overcome transient maternal effects, plants from aged pollen were significantly heavier than were other plants. This suggests that there is selective mortality among stored pollen grains. This may have both basic and applied implications.