Geranium flower pollination. Coloured scanning electron micrograph (SEM) of pollen grains (red) on the upper part of the female part of a geranium flower (family Geraniaceae). The female part of a flower is named the pistil, and the upper part can be one or several stigmas. A geranium pistil has 5 free stigmas, which have opened up here to expose their pollinating surfaces (yellow). A pollen grain contains the male genetic material and grows a tube down the pistil's central stalk (style) to fertilise the female genetic material in the ovary (not seen) at the base of the pistil. This forms a seed for a new plant.