Quercus robur Argenteomarginata - English Oak

The Quercus robur 'Argenteomarginata' is an unusual variegated form of our venerable Pedunculate Oak. Smaller and slower-growing, this tree has much more decorative foliage, as each leaf is finely edged with white on a green background. Rare in cultivation, this Oak is perfect for bringing light and creating a strong contrast in the garden. It prefers non-burning sun and rich, deep, and moist soils.

The Oak, in Latin Quercus, is a member of the Fagaceae family, like Beech and Chestnut. The Pedunculate Oak is a tree native to a large portion of temperate Europe. It grows well in sub-oceanic to oceanic climates or relatively humid continental climates without excess. This tree is commonly found in low-lying plains and hills but is rare in areas that are too dry and hot. There are around 240 named cultivars of the Pedunculate Oak, including 'Argenteomarginata'.

The Quercus robur 'Argenteomarginata' has a relatively slow growth rate. Its habit is rounded, slightly narrower than it is tall. At maturity, it reaches about 12 m (39ft) in height, and its crown measures 10 m (33ft) in width. The short trunk is initially green and smooth, then becomes dark, thick, and deeply fissured. The crown is irregular, oval, rounded, and open. Its young branches are glabrous, grey-brown, and shiny. The foliage, which is late deciduous, consists of alternate, soft, obovate leaves that can reach 5 to 15 cm (2 to 6in) in length and 3 to 8 cm (1 to 3in) in width. Each leaf is divided into 5 to 7 pairs of asymmetrical rounded lobes, separated by relatively deep sinuses. The base of the lamina is narrow and has two small lobes. The colour of the lamina is dark bluish-green on the upper side, with a more or less delicate cream-white border, creating a nice contrast. The underside of the leaf is paler. The leaves turn brown late in autumn and remain attached to the branches before falling. The flowering of this oak occurs in April-May, shortly after the appearance of the foliage on the annual shoots.

The female flowers are placed in a cupule carried by a long peduncle: this distinctive feature 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 oval and elongated acorns, measuring 1.5 to 3 cm (1in) 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 at maturity in September and October. The root system of this tree is deep and powerful, with both a taproot and extensive lateral roots, providing a solid and enduring anchorage in deep and compact soils.

The Quercus robur 'Argenteomarginata' will delight enthusiasts of rare trees and variegated foliage. More manageable than the king of the forest, this Oak will become a centrepiece in a medium-sized garden, planted as a specimen. It can be planted in front of a large shrub bed composed of conifers or small trees with dark foliage, such as a purple hazel or a 'Black Lace' elderberry. Note that deciduous oaks have the advantage of producing good, abundant leaf litter, which is favourable for the growth of plants that germinate under their canopy.