Rhamnus (Frangula) frangula (alnus)

Rhamnus frangula, also known as the Alder Buckthorn, French Buckthorn or Common Buckthorn, is a bush commonly found in our undergrowth, clearings, and forest edges, in wet environments, both in the lowlands and mountains. This large shrub adorns itself with deciduous foliage that is elegantly undulating, beautifully dark green, and nicely tinged with red in autumn. After its discreet spring flowering, the female plants produce small red fruits that turn black in autumn, which are sought after by birds. It will grow in any soil that retains moisture, this buckthorn works well in the creation of low-maintenance hedges, as well as being very useful for the small wildlife in our gardens when associated with other local species.

Rhamnus frangula (synonym Frangula alnus) belongs to the Rhamnaceae family. This species is widespread throughout Europe, but absent from the most northern and southern regions. There are at least two ecotypes of Buckthorn, the first populating wet environments on acid soil, and the second preferring drier locations and calcareous soils. In the horticultural trade, Buckthorn preferring wetter soils is generally found. It is a dioecious plant, meaning that there are male plants with staminate flowers but no pistil, and female plants with flowers lacking stamens but with a pistil.

This is a bushy shrub, with a rather loose and slightly spreading habit, supported by flexible and spreading branches. Slow-growing, the buckthorn will reach a height of 3 to 5m (10 to 16ft) with an equal spread (sometimes up to 6m (20ft)). Its bark is dark grey-brown on the outside but orange-brown on the inner side (visible when lifted or peeling), dotted with lenticels forming small light-coloured enlarged spots. The buds are covered with brown hair. The deciduous foliage appears in spring and falls in autumn. It consists of entire, elliptical to ovate leaves with smooth margins and prominent veins, measuring 4 to 7cm (2 to 3in) in length. The colour is a shiny dark green on the upper side, lighter and matte on the underside. They turn red in autumn before falling. The flowering occurs from May to July, taking the form of small clusters of tiny yellow-green to whitish flowers, without petals, highly attractive to bees. On female plants, in the presence of male plants, round fruits called drupes, measuring 1cm (1in), form. They are initially green, then red, and finally black when ripe in October. The bark and dried fruits of the buckthorn are traditionally used in European pharmacopoeia for their laxative properties. The fresh fruits, highly prized by certain animals such as deer, contain a compound with psychotropic properties.

Plant and cultivate this Rhamnus frangula 'naturally' in an unpretentious shrub bed or in a countryside hedge. It should not be missing in any naturalistic garden, where it can accompany other native or 'exotic' shrubs that are truly easy to grow: Lonicera xylosteum (Honeysuckle), Viburnum lantana (Wayfaring tree), Sambucus Black Lace (Black elderberry), Viburnum opulus Roseum (Snowball tree), Lonicera fragrantissima and L. tatarica (Honeysuckles), Rosa rugosa Rubra (Rugosa rose), Ribes sanguineum King Edward VII (Red-flowering currant), Mespilus germanica (Medlar), and why not a Vitis vinifera (Ornamental grapevine), the choice is vast!