This fragrant shrub is showing a mass of flower at the eastern end of the south Walk.
The mock orange genus Philadelphus contains approximately 40 species of deciduous shrubs from Europe, Asia and America. Their leaves are arranged in opposite pairs, and they have four-petalled, cup or bowl-shaped flowers borne either individually, or in racemes panicles or cymes. Many members of the genus are fragrant, which adds to their horticultural appeal. All are easy to grow, requiring fertile, well-drained soil in full sun or partial shade. P. delavayi can reach 3m in height, has toothed leaves, arching branches and racemes of fragrant, single flowers. It is a native of western China, south eastern Tibet and northern China, and was discovered and introduced into cultivation in 1887 by l’Abbé Delavay, a French missionary and botanist (1834 – 1895).