Quercus robur
The European Oak is Native to temperate Europe and temperate Western Asia. A long-lived species, with many specimens in existence today that are between 1200 and 1500 years old. The European Oak, is a common sight informal gardens and parks around Europe and can grow to 30 meters tall, has a widespread crown, on a sturdy, deeply fissured trunk.
Styles & Sizes: As bonsai, they make Medium to Large sized Bonsai in most upright forms, they also tend to be popularly used in forest groupings.
Position: The prefer a full-sun area, though at the height of summer some bonsai may prefer a dappled shade location. While they are hardy bonsai plants if winter temperatures fall below -4C then they are best over-wintered in an unheated greenhouse.
Feeding: Feed with a balanced organic feed, every two weeks if using a liquid feed, every other month if using a pelletised version or after the pellets have fully dissolved away. Feed the bonsai from early spring until the end of summer.
Repotting: Young Oak’s grow roots rapidly and need to be repotted every year. Older trees can be re-potted as necessary, generally, if the growth in the current year is not as healthy as it can be it will benefit from a repotting in the following spring. Use a well-mulched bark, sharp sand, in equal parts. Alternatively, you can use a mix of Akadama, Pumice in equal parts.
Pruning: Trim back shoots to leave 3 leaves on stem once the stem has fully extended. It is wise to make substantial pruning cuts late in the season, to avoid excessive sap ‘bleed.’
Wiring: The ‘clip and grow’ method is best for styling the Oak. If wiring is required, wire in autumn, and remove before spring sets in entirely.