Quercus robur Atropurpurea - English Oak

The Quercus robur 'Atropurpurea' is a purple form of the English Oak, much rarer than the cultivar 'Purpurascens'. The tree is characterised by a "stunted" appearance, foliage that varies in shades of purple throughout the seasons, and a compact and rounded habit. Its young leaves, heavily tinged with coppery red during bud burst period, gradually turn to velvety burgundy violet, then to greyish purple green in summer. A collector's tree for large gardens!

The English Oak, also known as the Pedunculate Oak, English Oak, Common Oak, or Gravelin depending on the region, belongs to the family Fagaceae. It is native to a large part of temperate Europe. This species thrives in sub-oceanic to oceanic climates, and even slightly continental climates, that are relatively humid. It is very common in our lowland and low-altitude hills, but rare in the Southern Alps and Mediterranean region, which are too dry and hot. In its natural environment, it can reach a height of 50m with a spread of 25 to 30m, while its trunk can measure up to 2m in diameter. With a relatively exceptional longevity, this oak can live up to 2000 years according to some estimates.

The Quercus robur 'Atropurpurea' will reach approximately 12m in height and 8-10m in spread after many years. This oak has a slow growth rate. Its habit is generally rounded, with a dense and rather closed crown. The short trunk is covered with a thick and deeply fissured grey and dark bark. Its young branches are glabrous and purple in colour, and shiny. The deciduous foliage is composed of alternate, soft, obovate leaves that can reach 5 to 15cm in length and 3 to 8cm in width. Each leaf has 5 to 7 pairs of rounded, variable-sized, asymmetrical lobes separated by more or less deep sinuses. The colour of the lamina changes from shiny coppery red to velvety burgundy violet, and then to greyish purple green in summer, with the underside being duller. The leaves turn brown quite late in autumn and remain attached to the branches before falling. This oak blooms in April-May, shortly after the appearance of the foliage, on the annual shoots. The female flowers, greenish-yellow in colour, are placed in a cupule carried by a long peduncle: this distinctive characteristic is the origin of the species name, pedunculata. The male inflorescences are elongated, pendulous catkins tinged with yellow. They are produced on older branches. The female flowers give way to ovoid and elongated acorns, measuring 1.5 to 3cm in length. They are often grouped in pairs or threes and attached to a long peduncle. A cupule covered with scales covers one-third of the acorn. The colour changes from green to brown when ripe, in September and October. The root system of this tree is deep and powerful, with both a taproot and a spreading root system, ensuring a solid and lasting grip in deep and compact soils.

The 'Atropurpurea' English Oak, rare and magnificent, will become one of the centrepiece of a large garden. Its purple-toned foliage pairs perfectly with the golden foliage of the 'Concordia' Oak 'Quercus robur 'Concordia'' and the 'Sunburst' Honeylocust Gleditsia triacanthos 'Sunburst', as well as the silvery foliage of the 'Liempde' Willow 'Salix alba 'Liempde'' and the 'Nivea' White Poplar Populus alba 'Nivea'. It should be planted in a prominent, isolated location. This tree also provides the advantage of providing pleasant shade, which reflects light in winter, and producing abundant leaf litter, which is beneficial for the growth of certain plants that germinate under its cover. Its fruits feed small animals such as squirrels and jays.

France, with 4.5 million hectares of Sessile Oak (Quercus petraea) and English Oak (Quercus robur), has 30 to 40% of the total area covered by these two species in Europe. It is the leading oak producer in Europe and the second-largest in the world, after the USA. France is the country of oaks!