Quercus palustris Green Dwarf - Pin Oak

Quercus palustris 'Green Dwarf' is a dwarf variety of the swamp oak. It has a compact and regular habit in a dense ball shape, grown on a more or less tall stem and suitable for smaller gardens. Its large deciduous leaves, deeply incised, dark green, remain on the tree for a long time, capturing attention with their brilliance and autumnal shades of red-orange. This deciduous tree is a very hardy species that grows easily in full sun or partial shade, in all types of moist and deep soils, even wet, well-drained and without limestone. It is highly resistant to pollution and requires virtually no maintenance except for pruning dead and damaged branches. Use it to highlight a small body of water in a row, decorate a container on a terrace or in a city courtyard, or in symmetrical planting to bring brightness and structure to flowerbeds.

Native to the eastern and central United States, Quercus palustris is a large tree in the beech family, which can reach a height of 20 to 25m (65ft 7in to 82ft) with a spread of 12m (39ft 5in), with a conical habit. The cultivar 'Green Dwarf' is a dwarf variety with a dense, compact ball-shaped habit, which is generally grown on a more or less tall stem. It is a Dutch selection by H. de Vroom, dating back to 1977. Of medium growth, it will not exceed 4m (13ft 1in) in height and 2.5m (8ft 2in) in spread. The leaves, deeply divided into 5 to 7 lobes, somewhat resemble maple leaves. They measure from 10 to 15cm (3.9 to 5.9in) in length and 5 to 10cm (2 to 3.9in) in width. Shiny green during the summer, they turn a beautiful autumnal shade of red-orange. Almost marcescent, the dry and brownish foliage persists on the branches until winter. This oak tree blooms quite early in spring, then produces very decorative acorns with a diameter of 2cm (0.8in), nearly round, in two years. Its trunk, very straight, is covered with a smooth, greyish bark, and its branches give rise to numerous slender and more or less thorny twigs, which earned it its name. This oak tree develops a taproot, but its root system is not very deep. It can live 90 to 120 years in the garden.

The swamp oak 'Green Dwarf' grows in any rich, well-drained soil, without excessive limestone, in an open position, where it will be visible from afar. This variety with an architectural habit will express its full potential as a specimen planted in the center of a perennial or low shrub flowerbed, or in a row of several subjects. The tree shows more harmonious growth when cultivated in sheltered conditions, without excessive competition. To surround it, choose for example small evergreen shrubby honeysuckles (Lonicera nitida, L.pileata), boxwood hedges, Spiraeas with beautiful autumn colours, or even ground cover roses.