Lilac 'Oliver de Serres'Syringa vulgaris Oliver De Serres Lilac Lilac Oliver de Serres produces large double mauve blue flowers in mid spring. These lightly fragrant blooms are rosy violet when in bud and held at the tip of the branches, where they attract bees and butterflies into the garden. Green heart shaped leaves. Annual mulching and fertiliser in autumn recommended, with summer watering required. Plant in full sun. This lilac has a strong upright habit. Height: 3 m