The Mandarin bonsai is a strictly indoor tree and should be kept in a bright, sunny location, such as a south- or east-facing window. While it is tolerant of typical indoor conditions, it prefers high humidity and warm, stable temperatures. Placing it in a sunny, humid spot will encourage strong growth and vibrant foliage. Note that the mandarin does not tolerate big drops in temperature well and ensure that it is protected from the wind and temperatures overnight do not drop under 10 °C. 

During the warmer months, it benefits from being placed outdoors on mild summer days, provided it is protected from harsh wind or direct midday sun. However, it must be brought back inside before temperatures drop or if there’s risk of stress from environmental changes. 

Mandarin bonsai likes consistently moist but well-drained soil. Water thoroughly when the top layer of soil begins to feel dry to the touch. Avoid letting the soil dry out completely, but equally important is avoiding overwatering, as this can lead to root rot and leaf drop. The tree is sensitive to poor watering habits and may respond to stress, low sunlight, or excess moisture by dropping leaves. Ensure the pot has good drainage and avoid letting water pool at the bottom. 

If you are a first-time bonsai owner, another way to water is by submerging the entire pot in water until the bubbles stop. If you choose this method, be aware that your bonsai may not need watering for another two to four days, but this will depend on the factors mentioned above such as soil type, pot size and climate.    

A mandarin tree also requires high humidity, and this can be achieved by placing a gravel tray under the pot, as well as using a mister to spray the leaves.

During the active growing season, from spring to early autumn, feed your Mandarin bonsai with a balanced liquid fertiliser every two to four weeks. You can start adding Chrysal Liquid Bonsai Feed to your water from March until October. Use Naruko Fertiliser Slow Release Bonsai Feed once every one to two months. In winter, reduce feeding or stop altogether, depending on the growth activity and light levels in your space. Avoid fertilising if the tree is under stress or showing signs of leaf loss, as this can worsen the issue.

The Mandarin bonsai grows vigorously, making it highly responsive to pruning. Regular trimming of new shoots helps maintain its shape and encourages dense branching. You can pinch or cut back shoots to two or three leaves during the growing season. Hard pruning to shape the structure is best done in early spring. The tree can be lightly wired, but care must be taken as branches are relatively soft and can scar easily if wiring is left on too long. Regularly check and remove wire within a couple of months to avoid damage. 

Training your bonsai using wiring is possible to create a lovely tree silhouette, and can be done any time of the year, but spring and summer are usually best when the branches are more supple and pliable. We recommend using wires with a thickness that matches the thickness of the branch: if the wire you choose is too thick you will damage the bark. If it is too thin, it won’t be effective. 

Repotting should be done every 2–3 years, ideally in early spring, just before the new growth emerges. Mandarin bonsai prefers a well-draining soil mix, such as a blend of akadama, pumice, and lava rock or a commercial bonsai soil suitable for indoor trees. During repotting, you can prune up to one-third of the root mass, but take care not to over-prune, especially if the tree has recently shown signs of stress. After repotting, place the tree in a humid, sheltered spot out of direct sunlight for a week to help it recover. 

Trees that are ready for repotting will require root pruning, a suitable new pot and appropriate soil mix.

When repotting, do not cut back the root mass by a large amount, and choose a well-draining soil mix that has a neutral or slightly higher PH value of 5-6 but not over 7. We tend to use a mixture of different speciality bonsai soils on our trees. Every species is different so please contact us for free soil-mix advice or to take advantage of our repotting service.