Single-flowered varieties of hollyhock such as these, Alcea rosea, have nectar and pollen, but not the froufrou many-petalled doubles. Guided by fine lines to the centre of the flower, insects suck the sweetness from nectaries that sit at the base of the sepals. These appear as a five-pointed star made visible by gaps between the base of the petals. Bumblebees get liberally covered in pollen grains from a central bottlebrush of anthers and stigmas, both of which mature at different times to ensure cross- rather than self-pollination.