Rhododendrons attract attention even from a distance with their magnificent flowers. What you are looking at, however, is not an individual flower but entire flower umbels (trusses) or clusters of flowers. These umbels, consisting of several flowerheads, can be pipe-shaped, funnel-shaped, bell-shaped or dish-shaped.
The classic form is the upright, compact umbel which is most clearly seen among the large-flowered hybrids and the Yakushimanum hybrids, whereas the flowers of other species may turn sideways or hang down gracefully, for example, Rhododendron williamsianum.
The individual flower consists of five to seven petals that have merged together. Five to sixteen stamens are equipped with rather sticky pollen. The ovary contains five to twenty compartments. Pollination is carried out by honey bees, bumble bees, moths and other insects