The Saucer Magnolia (Magnolia x soulangeana) is already in flower in London, following the mild winter. Magnolia trees and shrubs are members of a very large genus containing between 120 and 230 species depending on the classification system used. The genus is named after the French botanist Pierre Magnol. It is an ancient genus with ‘primitive’ flowers adapted for pollination by beetles. The petals, for example, are known as tepals because the sepals and petals are indistinguishable. This is a feature common to plants that appeared early on in the evolution of Flowering Plants. Magnolias are important horticulturally. They are now sold worldwide and many new varieties have been developed. They are grown for their beautiful flowers and their striking foliage. Two common Magnolias – the Saucer Magnolia and Star Magnolia flower in Spring and the Southern Evergreen Magnolia flowers from midsummer. See a previous post for more information.
The Saucer Magnolia, a deciduous shrub or small tree, is a hybrid between two Chinese species, Magnolia denudata (Yulan), which has white flowers and Magnolia liliflora, which has purple and white flowers. It was initially bred in 1820 in France by a retired cavalry officer Etienne Soulange-Bodin and was introduced to Britain in 1827. It is now the most popular and well-known form of Magnolia, widely planted in parks and gardens. It flowers in early spring, then through the summer. Photo taken in April 11 2019
Vase-like flowers first emerge in March, before the leaves but continue to emerge through the summer. Flowers are white with a pink or purple stain. Photo taken March 19th 2014. This year some flowers are already out in February.
In this photo some of the tepals have been removed to show the purple anthers and green styles of the sexual parts of the flower. The anthers release male pollen grains. Each style is connected to an ovary. For pollination to occur a pollen grain from another tree must land on the style.
Close-up of the flower centre after the pollen grains have been released by the anthers. In Magnolias pollination is mainly carried out by beetles. They are attracted to the flower by sweet-smelling secretions and may shelter and feed in the centre of the flower for several hours. If the anthers release pollen during this time, the beetle gets contaminated with pollen grains. Eventually the inner tepals open and release the beetle which then flies off to other trees and pollinates them.