Quercus petraea Purpurea - Sessile Oak

Quercus petraea 'Purpurea' is a purple form of the Sessile Oak, also known as the English Oak or Common Oak, which is very rare in cultivation. This tree differs from the typical form by its even slower growth and its magnificent foliage ranging from grey to purple and purplish-green. With a massive trunk, it has a wide canopy and thick, twisted branches located towards the lower part of the trunk. Its beautiful deciduous foliage provides pleasant shade in summer, although it will be future generations who will enjoy it. Interesting for wildlife, its acorns are a delight for many animals. A collector's tree that will delight enthusiasts!

Quercus petraea 'Purpurea' is a natural mutation of the sessile oak. The sessile oak, which is also known by various regional names such as English oak, durmast oak, rock oak, male oak, or black oak, belongs to the Fagaceae family. It is native to a large part of temperate Europe. It thrives in sub-oceanic to oceanic or continental climates, without extremes and not too dry. It is a spontaneous species found in hills and low mountains, where it can be found up to 1600 metres in altitude. More tolerant than the pedunculate oak, it can grow in rocky, slightly calcareous, and occasionally dry soils, although it prefers loamy-sandy soils that are neutral to acidic, moist, deep, and well-drained.

Quercus petraea 'Purpurea' grows slowly and typically reaches a height of 15 metres. In theory, this oak can live for several centuries. Deciduous oaks have the advantage of producing good quality and abundant leaf litter, which is beneficial for the growth of plants that germinate under their canopy. Its habit is rather massive, slightly wider than tall. The trunk, which is quite short, is initially green and smooth, but becomes dark, thick, and slightly fissured. The crown is irregular, oval, rounded, and open. Its young branches are smooth, grey-brown, and shiny. The foliage, which is late to shed, consists of long-petioled, alternate, soft, obovate leaves that can reach 5 to 15 cm in length and 3 to 8 cm in width. Each leaf is divided into 9 to 12 round and irregular lobes, separated by relatively deep sinuses. The colour of the leaf changes from grey to purple and then to purplish-green, with the underside being lighter. The leaves turn brown, quite 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 located in a cupule directly attached to the branch: this distinctive characteristic is the origin of the species name, sessile. The male inflorescences are elongated, pendulous catkins, tinged with yellow. They are produced at the base of the annual shoots. The female flowers, located in the axils of the leaves, give way to ovoid and elongated acorns, measuring 1.5 to 3 cm in length. They are often grouped in pairs or threes, directly on the branches. A cupule covered with scales covers about one-third of the acorn. The colour changes from green to brown when mature, in September and October. The root system of this tree is deep and powerful, with both a taproot and extensive lateral roots, ensuring a strong and durable anchorage in deep and sandy soils.

The purple sessile oak is a tree that will become the centrepiece of a park or large garden. It should be planted as a solitary specimen. Its magnificent foliage provides pleasant shade. Being deciduous, it allows light to pass through in winter. Its fruits provide food for small animals such as squirrels and jays. To accompany it, choose a variegated field maple 'Carnival', a London Plane Tree 'El Gordo', or a Greenspire Linden. The root system of oaks, which tends to be deep, allows for the planting of companion plants: consider, for example, bear's breeches, Trachystemon orientalis, periwinkles, Naples cyclamen, Liriope muscari, and more.