Lysimachia ephemerum - Willow-leaved yellow loosestrife

Lysimachia ephemerum, also known as willow-leaved loosestrife, is a tall and elegant perennial, and undoubtedly one of the most ornamental in the genus. It is clothed in silver and composed of stems covered with lanceolate leaves similar to willows. Its large floral spikes appear in summer, densely filled with small star-shaped white flowers with mauve veins. This robust plant thrives on the edge of water, especially on limestone soil. Its flowers can be cut to create beautiful bouquets.

Native to southwestern Europe, mainly Spain, Portugal, and France, this loosestrife prefers the vicinity of springs and colonises the limestone rocks and seeping areas of the Corbières, Dordogne, and the eastern and central Pyrenees. It belongs to the primrose family. From a thick and fibrous crown, it forms a bunch of sturdy, hollow, silver stems covered with narrow, elongated, beautiful almond-green leaves with silver highlights. The floral spikes reach a height of 1m (3ft) in July-August, at the top of the stems. They sometimes measure 30cm (12in) long and are composed of numerous small, white, star-shaped flowers, occasionally slightly tinged with violet, with mauve veins, and a diameter of 1cm (0in).

Willow-leaved loosestrife can be grown in flower beds and containers. It is perfect on the edge of water features or in damp rockeries, alongside cowslips, willowherbs, and vernonias. This plant is useful for its discreet yet effective presence in flower beds, where its upright habit and glaucous foliage highlight heavier plants or more vibrant blooms. It can sometimes become invasive if the conditions are suitable, self-seeding spontaneously in fertile, well-drained, and moist soil.