Rehmannia elata

The Rehmannia elata is a lovely perennial from China that can sometimes reach a height of 1 meter (3 feet) in our climates. Large basal rosettes, composed of toothed and fuzzy leaves, emerge in May from long, slender stems, carrying for several weeks large, bright pink tubular flowers with a widely open throat, yellow speckled with red, that surpass those of foxgloves and incarvilleas, and prove to be very long-lasting in bouquets. It thrives in partial shade, in dry soil all year round, even in winter.

The Rehmannia elata is a perennial with an often short lifespan due to overly moist soil, classified by botanists sometimes in the family of scrophulariaceae (like foxgloves and snapdragons), sometimes in that of gesneriaceae like Gloxinia and Saintpaulia with which it also shares certain characteristics. This plant is native to the Chinese mountains, which is a guarantee of hardiness. It has a creeping growth habit, due to its underground rhizomes that colonize the soil, giving rise to small rosettes all around the mother plant. Its growth can sometimes be very fast. The plant develops a rosette of semi-evergreen leaves, sometimes evergreen if the winter is mild, marbled with bronze and deeply veined. Reaching up to 1.50 m (5ft) in its native region, the erect clump it forms in our latitudes remains more modest in size, but exhibits from May, and sometimes until autumn, beautiful stems filled with large flowers, measuring 7 to 10 cm (3 to 4in) in length, reminiscent of bright pink foxgloves. The English even nickname this plant "Chinese foxglove". Some gardeners across the Channel have witnessed the Rehmannia reblooming in December, in the form of scattered small flowers, resting on the basal rosettes. In regions with hot summers, this decidedly curious plant prefers to bloom in autumn and winter.

The Rehmannia alata is primarily a plant for dry shade, preferring cool climates. It requires dry soil, even rocky, with not too much limestone, throughout the year. It will thrive at the edge of a woodland or under evergreen bushes that ensure constant soil drainage. We grow it alongside Francoa sonchifolia in the dappled shade of a Cupressocyparis hedge, where the soil is more acidic and always very dry, even in winter. When its foliage persists in winter, it adds some colour to the garden and occasionally adorns itself with a few flowers, at a time when they are rare in the garden. In partial shade and well-drained soil, it forms a good ground cover, like periwinkles, dead nettles, or perennial geranium macrorhizum. It can also be associated with the Christmas fern, which will provide a beautiful backdrop for its surprising flowering.