Hibiscus 'Blue Bird' (Hibiscus syriacus) - flowering shrub - 17 cm pot - Height 45 cm

Yes, theHibiscus syriacus 'Oiseau Bleu' is a fully hardy shrub, capable of withstanding temperatures down to -15 °C under normal growing conditions. It overwinters without any special protection in almost the entire territory of France, including the continental regions and USDA zones 6. You simply need to ensure well-drained soil in winter, as it is standing water around the roots that weakens it more than dry cold. Note: it breaks dormancy very late (May), which can worry novice gardeners, but this is completely normal for this species.

L'Hibiscus syriacus 'Blue Bird'flowers from mid-July until the first frosts of 'October, for a period of 10 to 12 weeks, exceptionally long for a shrub. Its large blue-purple funnel-shaped flowers with purple centers 'open continuously, each flower lasting only 'one day but being immediately replaced by a new one. This late summer bloom is valuable in the garden because it takes over from spring shrubs and fills the void of 'summer. To maximize the 'abundance of flowers, hard pruning in March and a full-sun location are essential.

At maturity, theHibiscus syriacus 'Oiseau Bleu' generally reaches 2 to 3 meters in height and 1 to 1.5 meters wide, depending on growing conditions and pruning. Its growth is moderate, around 20 to 30 cm per year. By pruning it regularly every spring, it can be kept at more compact dimensions, around 1.5 to 2 meters, while improving the density and abundance of the blooms. Its naturally upright and narrow silhouette makes it an easy shrub to incorporate even into small gardens.

Yes, 'Hibiscus syriacus 'Blue Bird' grows very well in a large pot on a terrace or balcony with full sun. Choose a container 'at least 40 to 50 cm in diameter with drainage holes at the bottom, and use a lightweight all-purpose potting mix with 20% perlite or fine gravel to prevent 'root suffocation. 'Watering must be more frequent than 'in the ground, especially in July and August. In winter, protect the pot from frost by 'wrapping it in horticultural fleece or moving it into a bright, frost-free area, as roots in a container are more vulnerable than those in the ground.

The pruning of 'Hibiscus syriacus 'Blue Bird' is 'done every year in March, before the buds open. It 'is advisable to cut back all the previous season's shoots by two-thirds of their length, cutting just above a well-positioned bud 'facing outwards. This annual pruning is essential because the flowers bloom exclusively on the current year's growth: the more vigorous the new shoots, the more numerous the flowers. A short pruning produces larger flowers; light pruning produces a larger shrub but with smaller flowers.

L'Hibiscus syriacus 'Blue Bird' pairs particularly well with warm-toned summer perennials that contrast with its blue-purple: 'yellow-orange daylilies, Rudbeckia, 'blue agapanthus, or even 'Hot Lips' create very summery displays. For a mixed flowering hedge, pair it with 'other cultivars of 'Hibiscus syriacus with white or pink flowers, such as 'Diana' or 'Woodbridge'. At the back of a border, it 'harmonizes with Miscanthus and light grasses that sway around its upright silhouette. Among shrubs, Buddleia or Lavatera complete the season of blue and mauve blooms.

The ideal time to plant the 'Hibiscus syriacus 'Blue Bird' in the ground is spring, 'from April to June, when the risk of frost has passed and the soil is warming up. It can also be planted in September to give it time to 'establish its roots before 'winter, provided that it is 'watered regularly until 'the first autumn rains. Dig a hole twice as wide as the pot and improve the bottom with mature compost. Position the crown exactly at ground level, without 'burying it.