The plant is very effective when growing as a bonsai. Its leaves are carmine-red with a yellow border, turning dark red by autumn.
It blooms in May with small yellow flowers, after which red berries are formed.
Ideal for bonsai growing as it easily adapts to forming and pruning to create a harmonious miniature tree.
Location
Full sun or partial shade.
In full sun (5-6 hours a day), the purple leaves are more intense, while those growing in semi-shade have a green color in the leaves.
Temperature regime
It develops best at a temperature of +18…+20 °C.
Lighting
In summer, at temperatures above +30 °C, the plant becomes susceptible to sunburn, so it is necessary to move it to the shade.
Soil
Barberry is undemanding to soil acidity, optimally 6.0-7.5 pH.
The required soil mixture consists of coarse sand and Akadama, and as organic components — crushed sphagnum moss, charcoal, humus, and garden soil. It is recommended to put drainage at the bottom of the container (see here).
Watering
A drought-tolerant plant, so watering is necessary only after the top layer of soil has dried out. It is useful to spray periodically with water and ensure good air circulation.
Fertilization
Fertilize barberry should be fertilized during the growing season from April to September 2 times a month. For abundant flowering, fertilizers with increased nitrogen, e.g., Biogold Original (see here), should be used.
After the buds start to form, switch to a fertilizer with an increased phosphorus and potassium content, e.g., Biogold Classic (see here). Fertilize once a month from mid-September and do not fertilize in winter.
Repotting
The ideal time for repotting is from late spring to mid-summer, as the warm weather will encourage the plant to grow quickly.
Shaping and pruning
Pruning should be done in the spring and summer. For formative pruning, 1/3 to 2/3 of the shoot length is removed. During fall pruning, weak, diseased and poorly developed shoots are removed.
Winterization
Occurs in a dark, cool room (basement, garage, cold pantry) at a temperature of 0 to +12 °C. In the winter period, watering is practically not required.
Thunberg's barberry is cold-resistant, tolerates frosts down to -5 °C.
In frosts additional covering is required to avoid root freezing.
Diseases and pests
Thunberg's barberry is mostly resistant to diseases, but can be attacked by aphids, pinworms and mealybugs. For prevention, you can treat the plant with a soap solution when pests appear.
