Cork Oak 150/175cm (5L)

The Cork Oak – Quercus suber is a remarkable evergreen tree celebrated for its distinctive thick, corky bark that has been harvested for centuries to produce natural cork. This specimen, supplied at 150/175cm in a 5-litre pot, represents the current size of a young tree ready to establish in your garden. Native to the Mediterranean region, just as hardy in this country, this characterful oak brings year-round interest with its dark green, leathery leaves that remain on the tree throughout winter, providing valuable structure and screening.

The most distinctive feature of Quercus suber is undoubtedly its deeply fissured, spongy bark that develops a rich, russet-brown colour as the tree matures. This corky layer can eventually reach several centimetres in thickness, creating extraordinary texture and visual interest. The glossy, oval leaves have a grey-green underside and serrated edges, creating a pleasing two-tone effect when caught by the breeze. In spring, the tree produces inconspicuous yellow-green catkins, followed by acorns that ripen over two seasons, providing food for wildlife.

Cork Oak thrives in well-drained soils and displays excellent drought tolerance once established, making it particularly valuable in drier gardens or those with free-draining sandy or gravelly conditions. It performs best in full sun where it can develop its characteristic spreading crown and robust root system. While naturally suited to warmer climates, Quercus suber can succeed in sheltered positions in milder regions, particularly in coastal areas or southern counties where winter temperatures remain relatively moderate.

This evergreen oak makes an excellent specimen tree for larger gardens, where it has space to develop its broad, rounded canopy. The year-round foliage provides valuable privacy screening, whilst the gnarled bark becomes increasingly architectural with age. Cork Oak also supports biodiversity, with acorns feeding birds and mammals, and the dense canopy offering nesting sites. The tree’s tolerance of coastal conditions and salt-laden winds makes it particularly useful in seaside gardens.

Care Guide

Plant your Cork Oak in a sunny position with well-drained soil. This species is not suitable for heavy clay or waterlogged conditions, which can lead to root problems. Dig a hole twice the width of the root ball and mix in grit or sharp sand if your soil is on the heavy side. After planting, water thoroughly and apply a mulch of bark chips or gravel, keeping it clear of the trunk.

Water regularly during the first two growing seasons to help establish a deep root system, but avoid overwatering. Once established, Cork Oak displays excellent drought tolerance and rarely requires supplementary watering except during prolonged dry spells. Feed young trees each spring with a balanced slow-release fertiliser to encourage healthy growth.

Cork Oak benefits from minimal pruning. Remove any dead, damaged, or crossing branches in late winter or early spring, but avoid heavy pruning as this species naturally develops an attractive shape. Young trees may require formative pruning to establish a clear trunk and balanced framework. Always make clean cuts just above a bud or branch junction.

Protect young trees from harsh winter winds and severe frost during their first few winters, particularly in colder areas. A fleece wrap or windbreak can help vulnerable specimens through their establishment period. Apply a generous mulch around the base each autumn to insulate roots and suppress weeds, but keep the mulch away from direct contact with the bark.

Cork Oak is generally pest and disease resistant, though young foliage may occasionally attract caterpillars or aphids. Monitor regularly and treat only if infestations become severe. The thick bark provides natural protection against most problems as the tree matures.

Ultimate height
Higher than 12 metres

Time to ultimate height
20–50 years

Ultimate spread
8–12 metres