Hibiscus syriacus Beautiful Cobalt - Rose of Sharon

Hibiscus syriacus Beautifull® Cobalt 'Minsybfcble17' has captivating deep blue, large, double-centred flowers, which bloom consistently from summer through autumn on the current year's wood. This variety of Rose of Sharon, with its upright habit and strong stems, makes a striking presence in the garden, whether planted as a specimen, in an informal hedge, or in a large pot. It offers a fine balance between exotic appeal and hardiness, as it tolerates both intense heat and harsh winters. It is a generous, decorative, reliable plant, suitable for both city gardens and more natural settings.

Hibiscus syriacus Beautifull® Cobalt ‘Minsybfcble17’ belongs to the Malvaceae family. It is also known as Rose of Sharon, shrub althea, or tree mallow. The species Hibiscus syriacus, also called Althaea frutex or Ketmia syriaca, is native to eastern Asia, mainly China, Taiwan, Korea, and northern India. It is a deciduous, hardy shrub with significant longevity and a deep root system.

The ‘Minsybfcble17’ cultivar, marketed as Beautifull® Cobalt, was developed in France by Hortival Diffusion in 2024; it is an improved selection of the Blue Chiffon® variety. It belongs to the Beautifull® series, characterised by better repeat flowering, a more branched and upright structure, reinforced stems that support the flowering well, and clean flower drop with few fruits formed.

Beautifull® Cobalt is a compact, naturally upright shrub with strong stems that become woody by the second year. It reaches about 3m in height and 1m in width at 10 years when planted in the ground. In a container, height generally remains under 2m, depending on pot size and pruning frequency. The foliage yellows and drops in autumn, then regrows in spring. The leaves are single, alternate, trilobed, measuring between 5 and 10cm long, with a toothed margin and a clear mid-green colour.
The flowering period extends from July to October, with excellent repeat performance. The flowers appear solitary in the leaf axils and measure 8 to 10cm in diameter. They are semi-double, with a centre composed of petaloids. Their colour is an intense blue, tinged with mauve, with a throat veined in garnet red. The style and stamens are cream to ivory, grouped in a tube typical of the Hibiscus genus. The flowers are scentless but highly attractive to pollinating insects. The plant produces few fruits, which prolongs flowering and limits debris after blooming. The stems of this Rose of Sharon are robust, cylindrical and grey-brown with a smooth surface in the early years, becoming more marked with lenticels and striations with age. The bark cracks slightly as it matures.

Adorned with velvety cobalt blue blooms, Hibiscus syriacus Beautifull® Cobalt brings a theatrical quality to summer scenes, especially in strong light. Place it as a backdrop to a bed of bush sages, beside a Chaste Tree or a compact Crape Myrtle, to create a vibrant display in the sun. For a softer atmosphere, pair it with Russian Sages, catmints, and a Wisteria trained as a standard: its intense blue colouring will evoke a Provençal fresco. In a container on a south-facing terrace, it can be combined with cloud-like grasses or softly structured cosmos. This plant has character, so give it a setting to match!