Frankenia laevis

The Frankenia laevis, also known as Smooth Frankenia, is perhaps better known as seaside heather. This tiny evergreen coastal plant with dark, curly foliage and pink flowers can indeed resemble a very low-growing heather. It quickly develops into a wide carpet, like a true vegetal mat, and takes on beautiful red to violet hues when exposed to cold weather. This ground cover can withstand moderate trampling, heat, relative summer drought, and requires no mowing. It can be used as an alternative to grass on small surfaces, provided it is installed alone, away from any competition, in a well-drained soil and in full sun. Charming in the joints of paving stones and retaining walls, it fills the spaces between rocks in rockeries and adorns pathways. 

Native to Atlantic and Mediterranean coastlines, Frankenia laevis is a botanical species belonging to the little-known family of frankeniacs. Most often classified as a perennial, it is actually a prostrate and creeping undershrub. In nature, it is found in rocky and well-drained areas, especially on sandy soils, by the seaside. Its hardiness is around -12 to -15°C (10.4 to 5°F) in perfectly drained soil. Its drought resistance is rather good, but in a Mediterranean climate, the plant will require ample watering once a week to stay beautiful. Its habit is carpeting, its stems root upon contact with the ground, allowing it to quickly cover the ground with a network of leafy stems, up to 2 to 4 cm (1 to 2in) tall and at least 50 cm (20in) wide. Very pleasant if the soil remains moist, the carpet becomes more brittle and fragile during dry periods. The evergreen foliage is composed of tiny dark green leaves that take on lovely shades in autumn and winter. The abundant flowering occurs from May-June to July, depending on the climate. Tiny single flowers in light pink with a yellow centre bloom at the end of the shoots. Note that Frankenia laevis requires regular manual weeding, as it fears competition from weeds as well as other ground cover plants.

Frankenia laevis is decorative all year round, offers great resistance to parasites, diseases, sea spray, and drought, but its hardiness is quite limited, making it suitable for mild regions. Its densely carpeting habit makes it an ideal plant for elegantly filling in the joints of paving stones, cracks and tops of walls, or the edges of a stone staircase. It can be paired with Nepeta mussinii, Geranium sanguineum, Lithodora, Teucrium, and other non-invasive cushions. Since it tolerates moderate trampling and salt, it is often used as a replacement for lawns in coastal gardens with poor, sandy soil, on surfaces ranging from 50 to 100 m².  Seaside heather dresses up the ground near flower beds, along pathways, and will thrive in a sunny rockery, alongside aubrieta, golden or silver baskets, thyme, and creeping ceanothus.