Berberis thunbergii
The Barberry is a deciduous, compact, spiny, shrub native to Japan. Widely grown as an ornamental plant, in the northern hemisphere, for purple summer foliage and fiery orange-red in autumn colour. It has tiny delicate leaves, inconspicuous yellow flower and little red berries.
Styles and Sizes: As bonsai, they make medium to large bonsai in most upright styles.
Position: A versatile plant it can take on a range of conditions, but a prefers a sunny position, which will encourage colourful winter foliage and profuse flowering and fruiting.
Watering: It loves a moist soil but does not like it root wet all the time so ensure the bonsai is watered well early morning to it has the water when it needs it most, and the pot, un-saturated into the night.
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. Begin feeding when the leaves have entirely greened up usually from mid-spring onwards. If the summer is regularly hot, above 30°C, then hold off feeding.
Repotting: Young Barberry grows roots rapidly and is best repotted every year. Older bonsai 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, use a mix of Akadama and Pumice in equal parts.
Pruning: Trim back current years growth to leave three lateral shoots or active leaf buds. Structural pruning on more massive branches is best carried out late in the year at the end of autumn or early winter as this species “bleeds” profusely.
Wiring: The Barberry is best trained using the clip and grow method.