Holm Oak – Quercus Ilex

Holm Oak Tree General Information

Holm is another word for Holly and the Holm Oak is often called the Holly Oak as its leaves are very similar to those of a holly bush.  The Holm Oak is a large evergreen, native to the Mediterranean region and is thought to have been first introduced into the UK in the 16th century.

This hardy tree has a beautiful rounded canopy and low hanging branches, with its shape and size giving a lovely architectural presence.  Added to this, its ability to tolerate shade and air pollution make it a very popular tree for public parks, city and suburban streets as well as gardens.

The Holm Oak is a slow growing tree prized for its very hard wood and has been used for making pillars, wagons, boats, tool handles and furniture.  Used as firewood the timber is often collected to make charcoal.

The Holm Oak can live for about 400 years and reach between 65 to 70 feet in height when mature.

Description of a Holm Oak Tree

The bark of a young Holm Oak is smooth and light green or grey in colour, darkening with age and becoming furrowed.  Leaves are a shiny dark green and leathery in texture, although the bottom of the leaves have very fine hair and are a silvery colour.  Resembling holly leaves and with prickly edges, as the tree mature these sharp points disappear as the leaf edges soften.  An evergreen tree, old leaves fall 1-2 years after the new leaves have emerged.  The Holm Oak also has a large spreading leafy canopy and a thick trunk.

The flowers are very small, elongated yellow catkins with both male and female flowers on the same tree.  Pollinated by wind, the female flowers develop into acorns.  These acorns are very similar to a standard acorn and sit within a scaly cup.  Green when young they turn a reddish brown when they mature and fall in the autumn.

Cultivation of a Sycamore Tree

Preferring a moist to dry soil of sand or clay the Holm Oak has the unique ability to be able to grow in full shade.  Although the Holm Oak can tolerate high winds and withstand maritime conditions, including salt air, it cannot survive in regions with freezing temperatures and fairs much better in the south of the UK.  Adding ornamental value to a variety of landscapes, the Holm Oak does best on seaside properties and makes an excellent windbreak.

Pests and Diseases of a Sycamore Tree

Due to being a hardy species the Holm Oak is not susceptible to many diseases and is generally disease free but a few that can attack are, root rot, which happens if the root system is made to stand in water for a long period of time, the symptoms include fungus growing on the tree roots which can then spread to the trees bark and branches. Wilt, which is a serious disease, affects the trees leaves, stunting foliage and turning it yellow.  Other symptoms include leaf curling and leaves dying and dropping prematurely.

A pest affecting this tree is the Holm Oak leaf mining moth, for which there is no control.  Fortunately, even when heavily infected by the pest, the Holm Oak withstands the damage caused and continues to grow.  Aphids can also be a problem with this particular tree.

Pruning the Holm Oak Tree

Due to the Holm Oak being a rather dense tree regular thinning is recommended to increase air circulation and pruning will keep this tree a manageable size.

Article Source: http://www.graftingardeners.co.uk/holm-oak-quercus-ilex/


  1. How near to a permanent dwelling should a holm oak be? It is already at a height of 20feet plus and the Tarmac surround on the drive has cracked & is lifting making the ground hazardous. It also has a TPO.
    Thank you for any advice.

  2. Thank you for your very informative notes. Excellent!
    Is it possible to prune it annually from planting, to keep it as a very small tree, perhaps max. of 2.5 metres high and similar spread?
    We would LOVE to have one but can’t allow it to grow much bigger.
    Your advice would be GREATLY appreciated.

    1. Good Question Homayoon,

      Pollination will begin during May and the acorns will fall off around mid-September.

      This means it will take about three and a half months for the seeds to fall and it will also take another month for the tree to drop all of its acorns.

      Hope this helps.


      GraftinGardeners Team.

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