Rudbeckia triloba Prairie Glow

The Rudbeckia triloba 'Prairie Glow', related to the large echinaceas, is a tall and extremely generous plant, which will quickly make an impact in a large rustic bed, natural or in a wildflower meadow. Remarkably floriferous, 'Prairie Glow' shines with a thousand flowers resembling small tricolor suns, in red-orange, yellow, and black, which succeed each other from mid-summer until the frosts. Loved by insects and birds, this wild-looking plant will be much appreciated by gardeners. In autumn, the flowering mixes with that of tall asters and the colours of autumn. Although it grows quickly, this rudbeckia does not live very long. However, it self-seeds quite easily in the garden. 

The Rudbeckia triloba belongs to the asteraceae family. This plant native to central and eastern areas of the USA grows in the wild, in rather humid places that are not too dry, in open areas, and in disturbed spaces such as roadside edges and fallow lands. It is a short-lived perennial (2 to 3 years) most often considered a biennial. Fresh seeds germinate very quickly in autumn, the plant overwinters as a rosette and forms a beautiful clump in a matter of weeks. The 'Prairie Glow' cultivar was recently obtained in the USA by the American breeder David Cavagnaro.

At maturity, this Rudbeckia forms a clump of leafy stems that will reach about 1 m (3ft) in height and 50 cm (20in) in width. The leaves of the rosette located at the base of this plant are divided into three lobes. On the other hand, the leaves of the stems, arranged alternately, are coarsely toothed. The very rigid stems are dark red in colour and have white hairs. They branch out and bear, from July to October-November, numerous inflorescences organized in heads, and which we call 'flowers'. Each head, about 4-5 cm (2in) wide and with a simple shape, almost naive, has 8 to 9 ligules in red-orange colour with yellow tips, arranged in a collar around a slightly prominent black centre in a conical shape. Under good conditions, a single plant can produce up to eight highly branched flower stems. This nectar-rich and honey-rich flowering is highly visited by pollinating insects. The seeds left in place attract birds, feeding goldfinches and tits at the beginning of winter. The Rudbeckia triloba is anchored by rather short fibrous roots, unsuitable for long periods of drought. 

Take advantage of the generosity of the rudbeckia to associate it with ephemeral flowering plants within a « mixed border » in the style of cottage gardens. Choose varieties with softer, almost pastel shades to calm or even tame its conquering colours. Positioned in the background, it will be most effective with tall asters (Aster laevis Calliope, Aster turbinellus), grasses (Panicum virgatum, Miscanthus), and landscape dahlias bulbs (varieties Bishop of Dover and Bishop of York) and a shrubby artemisia. Planted en masse in front of shrub beds, the Rudbeckia 'Prairie Glow' will be magnificent combined with the autumn foliage of deciduous euonymus, cotinus, hydrangea quercifolia, parrotia persica.