Rehmannia Polina

The Rehmannia 'Polina' is a rare Chinese perennial with erect stems, producing from spring to autumn large ivory-white tubular flowers with a yellow throat, giving it an exotic appearance. Hardy, it requires a well-drained soil to thrive but can tolerate periods of drought and can grow in light sun or partial shade.

This curious species belongs to the no less curious family of Orobanchaceae, which includes mostly semi-parasitic plants like broomrapes or louseworts. Stiff stems emerge from a rosette of wavy, dark green and semi-evergreen leaves, roughly toothed. Together, they form a sparsely leafy clump about 60 cm (24in) tall and 45 cm (18in) wide. Over a long period, from May to October, the 'Polina' variety produces beautiful ivory-white tubular flowers with a yellow throat, large in proportion to the plant, resembling the flowers of incarvillea. The petals are widely recurved, allowing pollinators to land easily on the edge of the corolla.

The Rehmannia 'Polina' is dedicated to ballet dancer Polina Semionova. It will thrive in moderately rich soil, in partial shade or in the sun, but most importantly, it requires good drainage; in heavy soil, its longevity will be significantly reduced, and its hardiness may be compromised however, it can withstand periods of drought.

It can be paired with plants that like rocky conditions (in not too scorching sun), such as Lychnis coronaria, Veronica liwanensis, or Calamintha nepeta. It will bring its exotic touch alongside neighbors like houseleeks, uncommon sedums (Sedum palmeri or S. rubrotinctum in mild climates) in the sun, or stinking hellebore in a shadier context. It is also possible to cultivate it in a pot, in a "mini-rock garden".

Rehmannias have long been used in Chinese pharmacopoeia under the name Shu Di Huang. They are believed to combat diabetes and fevers.