Cork Oak

Cork Oak (Quercus suber) is the evergreen oak with the thick, deeply fissured bark that cork is cut from. In a garden it makes a broad shade tree of about 10m tall and 8m wide over several decades, holding its leaves all year. It is also one of the toughest trees we sell: frost hardy, drought tolerant, heat tolerant and content on poor soil.

Why you'll love it

• Bark you plant it for. The corky, deeply furrowed trunk thickens with age into something closer to sculpture than timber.
• Evergreen shade. Unlike the deciduous oaks it keeps a full canopy through winter, so the shade is there all year.
• Genuinely hardy. Frost hardy, drought tolerant, heat tolerant, wind tolerant and happy on poor soil, a rare combination in a shade tree.
• Slow and long lived. It takes decades to reach full size and then holds it for generations.

Where it works best

Shade tree. A mature canopy of about 8m across covers a seating area or a good part of a lawn.

Driveways and avenues. Space trees about 8m apart so each canopy has room to develop its natural spread rather than crowding the next.

Windbreak and feature planting. It is wind tolerant, so a row along an exposed rural boundary filters wind well. As a single specimen it earns its place on bark alone.

Growing Cork Oak in Australia

Position and climate. Full sun, and plenty of room. It suits Mediterranean, warm temperate, cool temperate and arid gardens, which covers most of southern and inland Australia, and it is frost hardy once established. It is not a tree for tropical or subtropical gardens.

Soil. Drainage is the one real requirement. It tolerates poor, stony and shallow soil, but will not accept waterlogging, so on heavy clay plant on a raised mound and avoid low spots that hold water.

Water and feed. Water deeply once or twice a week through the first two summers, then step back: after that it needs no irrigation in most gardens. A complete slow release fertiliser in early spring for the first few years is enough.

Pruning. Very little. Remove crossing or damaged branches early to build a clear trunk and a balanced crown, then leave it alone. Do not strip bark from a garden tree, since the cork layer is what protects it.

What to expect when it arrives

It is grown in 400mm pots and in 45L and 100L containers. The 400mm plants are young trees, a single leader a metre or two tall, and the value choice if you can wait. The 45L and 100L trees arrive with a formed trunk and real height on day one.

Expect slow, steady growth rather than a quick result. Plants are packed to travel upright and delivered Australia wide, with delivery from $29.95 and a minimum order of $300 before delivery. Advanced and large stock is freighted at cost, and every plant carries our 30 day healthy plant guarantee.

Plant care guides and related reading

• Browse the advanced tree range
• The best canopy trees for shade
• Compare driveway trees for an avenue
• Other drought tolerant plants

Common questions

How fast does it grow?

Slowly, and that is the honest answer. Figure on a decade or more before it reads as a shade tree, and several decades to reach about 10m.

Can I harvest cork from it?

Not realistically in a garden. Commercial cork is stripped from mature trees on a nine to twelve year cycle by people who know how to do it without killing the tree.

Are the acorns a problem for dogs?

Acorns are toxic to dogs if eaten, so it is worth knowing before you plant one over a run or a play area. Mature trees drop acorns in autumn, and raking them up is the simplest answer.

Will the roots lift paving?

Any tree of this size needs room. Keep it at least 5m from paths, driveways and drainage lines, and give the root plate space rather than boxing it in with hard surfaces.