Bonsai
cultivation notes
Position
Full sun and good air circulation. Protect from hard frost below
-5°C. Shaded branches on Oak bonsai have a tendency to die-back.
Feeding Every two weeks at half strength after first growth
has hardened off in Spring.
Repotting Standard practice says that Oak should be repotted
yearly as buds start to move in Spring until the tree is 10 years
or older, then every 2-3 years. However, it is possible that repotting
after the first leaves have opened or in early Autumn is better
for Quercus robur/English Oak. Collecting
and Repotting English Oak
Pruning Trim new shoots and pinch out apical buds unless
extension is required.
Defoliation
Complete defoliation can result in larger leaves and
on weaker trees, dieback of lower branches. Infrequent repotting
helps reduce leaf-size, as does removal of apical/terminal buds
before they extend in Spring.
I have had very good results from regular removal of all large
leaves (except those on the weakest branches) and thinning of
the foliage at the tips of branches. The tips of most Oak branches
will produce a swirl of 4,5 or more leaves, remove all but the
smallest to prompt creation of a new flush of smaller leaves.
Propagation Sow seed outside as soon as ripe. Air-layering
with difficulty.
Pests and Diseases Very susceptible to mildew problems
unless good air circulation is provided, also oak wilt, aphids
and gall wasps.
Styles Upright and slanting styles, multi-trunk styles,
group planting in medium to large sizes. Suitable for subtle deadwood
features.
Pots
Glazed in light and textured, earthy colours.
Q.
robur leaf 
Q.
petraea leaf 
