Hibiscus syriacus Admiral Dewey

Hibiscus syriacus 'Admiral Dewey' is an elegant variety of tree mallow that produces beautiful white double flowers. Its large funnel-shaped corollas have an additional collar of petals in the centre. It softens the bright colours in the garden and highlights pastel tones with its immaculate white blooms. And the flowers of this flowering shrub are renewed from mid-summer to the beginning of autumn, as long as the weather remains mild. It is hardy and undemanding in terms of soil and will fit in all gardens.

Hibiscus syriacus 'Admiral Dewey' is a horticultural creation. The species, sometimes called Syrian hibiscus or garden hibiscus, is a hardy deciduous shrub in our climates, but evergreen in warm climates. It belongs to the Malvaceae family, just like hollyhocks and marshmallows. It is native to temperate regions of Asia (China, India) and has given rise to numerous cultivars, including 'Admiral Dewey'. In a few years, it forms a 3m tall and 1.50m wide upright shrub, supported by an erect but branched structure. Regular pruning can keep it at more modest dimensions and give it the appearance of a large bush. It blooms from July, sometimes earlier depending on the climate. Its ephemeral flowers, which wither in 24 hours, continuously renew until October. They are 8-10 cm wide and composed of numerous pure white petals arranged around a white throat. Its foliage is a bright green, slightly glossy, and turns yellow in autumn. The leaves are alternate, simple, heart-shaped, and trilobed; their edges are toothed and wavy.

The 'Admiral Dewey' tree mallow appreciates bright, warm exposures and can tolerate light shade in southern regions. Plant it sheltered from strong winds, in soil that remains moist during the peak of summer. This superb variety can be used as a medium-sized hedge, in combination with other hibiscus of different colours, with butterfly bushes, English shrub roses, and Crape myrtles. It can also be planted as a standalone specimen or at the back of a perennial bed, alongside daylilies, catmints, and shrubby salvias, for example.