Quercus robur Posnania - English oak

Quercus robur 'Posnania' is a magnificent tree distinguished by the beauty of its foliage and elegant posture. This pedunculate oak, with its spreading and fairly dense crown, only reaches about ten metres in height, making it suitable for integration into many landscaping and urban designs. The charming and delicate, elongated leaves, cut into narrow strips, can reach up to 25 cm in length. Hanging down, they give this variety a distinctive appearance compared to other oaks. Resistant to frost, this highly decorative oak grows in most soils as long as they are sufficiently moist, as it does not tolerate drought, which slows its growth. When planting it in the garden, it is important to choose a clear location to admire it, as it then takes on the appearance of a beautiful, eye-catching specimen.

Quercus robur, commonly known as the pedunculate oak, can also be called the common oak, cluster oak, female oak, or gravelin, depending on the region. It is a tree from the beech family, along with beech and chestnut trees. In Latin, Quercus robur means "robust oak". It is native to a large part of temperate Europe. This venerable tree appreciates sub-oceanic to oceanic or continental climates, without excessive heat and relatively humid. In its natural habitat, it can reach a height of 50 m with a spread of 25 to 30 m, while its trunk can measure up to 2 m in diameter. With fairly exceptional longevity, this oak can live up to 2000 years according to some estimates.

The 'Posnania' cultivar was selected in 1998 by Ewa Jerzak, a Polish breeder. This variety is the result of natural selection from seeds of an English oak 'Laciniata' from the Botanical Garden of Adam Mickiewicz University in Poznań, Poland. It was introduced to the market in 2011 by Joanna and Bronisław Szmit nurseries, located in Pęchcin, north of Warsaw, and was awarded an "Honorable Mention" at the New Plant Competition of the "Green is Life" International Exhibition in Warsaw that same year. Quercus robur 'Posnania' can reach a height of 10 to 12 metres and a spread of 7 to 9 metres, with a dense, spreading, and drooping crown. The deciduous leaves are laciniated with 5 to 7 lobes and can measure up to 25 cm long. The pendulous leaves give this variety a weeping form. They are dark green on the upper side and grey on the underside, with yellowish veins, and then turn beautiful yellow hues in autumn. This pedunculate oak develops early, rather insignificant flowers in early spring, which then give way to elongated acorns measuring 2 to 3 cm in length, light brown when ripe. However, they are not very numerous on this variety. 'Posnania' has a deep root system, based on a taproot and a significant network of spreading roots, which gives it stability and good anchoring in the soil.

The pedunculate oak 'Posnania' is a remarkable specimen that grows freely, requiring sufficient space for its proper development. Thanks to its elegant appearance and original foliage, it brings a new and unique touch to your space. It is a robust tree that can withstand winter cold, withstanding temperatures down to -32°C. It grows faster in fertile and moderately moist soil. Alkaline limestone soils are not suitable for this tree species. It can be planted alone as a specimen to admire its stature or in groups to create a grove with dappled shade. It is also recommended in urban environments for large gardens, parks, streets, squares, and large lawns. Why not accompany the pedunculate oak 'Posnania' with trees with similar requirements such as maples, beech trees, ash trees, linden trees, or even sophora trees to bring diversity in form, colour, and architecture to a large space? Ground cover plants suitable for shaded conditions and slightly moist soils can also be planted at its base, such as Japanese spurge (Pachysandra terminalis), Algerian ivy (Hedera algeriensis Algerian Bellecour), Greater periwinkle (Vinca major), or lady fern (Athyrium filix-femina). Being well-suited for pruning, it is suitable for bonsai shaping.