How does pollination take place in pea flowers?

Pea flowers are self-pollinating. About two days before the flower even opens, the anthers at the top of the stamen, which are the male part, burst and release the pollen. This sticks onto the stigma and fertilizes the ovary - these are the female parts. In many flowering plants, the stigma will not accept pollen from the same plant and fertilization must occur through other means, such as insect pollination after the flower opens. For gardeners, self-pollination is an advantage as it means more than one type of pea can be grown close together, as cross-pollination will not occur.