Physocarpus opulifolius Red Baron - Ninebark

Physocarpus opulifolius 'Red Baron' is a variety of Ninebark with a compact and sturdy habit, adorned with foliage in rich and changing colours. Evolving from golden bronze in its youth to almost black purple at maturity, its beautiful satin and toothed leaves create a beautiful two-tone effect on the plant, which is further enhanced by a charming flowering in early summer, in small white-pink umbels. In autumn, this bush is adorned with almost black leaves and red fruits. Superb in a container, this Ninebark is also magnificent in borders or in a low hedge.

Physocarpus opulifolius belongs to the Rosaceae family and is native to the eastern United States, up to Quebec and Manitoba. This shrub has a medium to fast growth rate and will not exceed 1.60m (5ft) in all directions when fully grown.

The Ninebark 'Red Baron', from which it originates, is quite similar to the 'Diabolo' variety in terms of color, but it is more compact. It is a deciduous shrub, highly branched and densely bushy in habit, initially erect and then arching with age. Remarkable for its young leaves that emerge in a golden bronze hue, it becomes even more astonishing as they gradually turn very dark purple throughout the growing season. The leaves are lobed, deeply cut, serrated, and measure from 3 to 8cm (1 to 3in). The spectacle of the foliage continues when the flowering occurs, from May to July. It takes the form of flattened corymb inflorescences adorned with purple buds that open into small white to pinkish flowers, nectar-rich and highly visited by pollinating insects. They are followed by red fruits in the shape of small bladders that birds appreciate in autumn. The shrub, devoid of leaves in winter, remains ornamental with its bark peeling off in beige to reddish-brown patches.

The 'Red Baron' Ninebark, with its striking appearance, will find its place in a large pot on the terrace or in borders, creating contrasts with shrubs with light or golden foliage. It will be charming within a low-height informal hedge, accompanied by spireas (Spirea arguta, Spirea x billardii), modest-sized viburnums, dwarf winged Euonymus (Euonymus alatus compactus), or a Neillia affinis that it will illuminate. To accompany its changing colors, one can plant Heucheras or Heucherellas at its base, for example.

The name of Physocarpus opulifolius comes from the Greek word 'phusa', which means air bubble or vesicle, and 'karpos', which refers to the fruit, in reference to the shape of the fruit. The resemblance of its foliage to that of the Common Ninebark earned it the specific name "opulifolius". Introduced to Europe around 1687, the numerous vibrant cultivars created in recent years have allowed it to make a strong comeback in gardens.