Tree Position (Indoor): Keep your bonsai indoors in a very bright room near but not directly in front of a sunny window. Be mindful of too much sun or shade. A few hours of morning or late afternoon sun is beneficial. (rotate the bonsai every few weeks if one side receives no light). Don’t place the bonsai near any heat source such as a fire, heater or heat pump. Open a window so the bonsai may receive adequate air flow from time to time. Occasional misting of the leaves is beneficial.
A note on indoor bonsai: A tree itself is not an indoor or outdoor bonsai species. The term indoor & outdoor is used to differentiate the two places a bonsai tree can grow based on your climate. A tree will grow always grow well in its native climate. If you grow a bonsai that is not native to your country (such as a ficus for example) and your country has a colder climate, then the ficus will need to live inside because it is too cold outside for it. You can probably see now that no tree is really an ‘indoor' type of bonsai, you are just mimicking the trees natural climate by placing the tree indoors. Certain indoor species such as Ficus live quite happily outside through the warmer months if shaded a little, or they can be grown inside year-round.
Watering: Ensure that the soil is always slightly damp but not drenched. How often you water your bonsai will depend on the weather, how deep your bonsai pot is. Keep an eye on your bonsai during hot days. Use your finger to check how damp the soil is before watering. If it feels a quite dry, then go ahead and water thoroughly. Wait a minute after watering, then water again. Be mindful not to over or under water your bonsai.
- Liquid feed every two weeks using a balanced fertiliser such as 'Nitrosol' or ‘McGregors Vege & Ornamental’. Halt feeding in Winter.
- Apply liquid seaweed tonic every other month for plant health. You can mix this in with your Nitrosol or VegeMax feed.
Always follow the directions on the fertiliser packet, and water the bonsai thoroughly before feeding to avoid root burn. Only liquid feed during the growing season (spring-autumn). Do not fertilise if the tree is weak or diseased. Lastly, do not fertilise newly re-potted trees for at least a few weeks.
Re-potting: Re-pot your bonsai every 1-2 years during spring. You can trim up to one-third of the roots before your bonsai goes back into the bonsai pot. Place the bonsai in a sheltered and slightly shaded spot for a week or two after re-potting. At this crucial stage, we want to shelter the bonsai from the hot sun, heavy rain, frost, snow, and wind. Lastly, be careful to not over-water your bonsai after re-potting. Re-pot using a fast draining soil mix. To make this, combine potting mix with pumice.
Pests and Diseases: Inspect your bonsai closely every other week for any sign of pest or disease. ‘Yates Bug Oil’ is recommended for pests. ‘Yates Fungus Fighter’ is recommended for mildew, black spot, and some other diseases.
Trimming: Trim back growth every few weeks when your bonsai starts to get out of shape during the growing season (spring to autumn) When making a cut, use sharp scissors and aim to cut right above a leaf node The overall tree shape that you should aim to create is a triangular silhouette. When your bonsai grows too dense, you will need to thin out the foliage by removing excess stems. This will encourage light and air to enter the centre of the tree.
Pruning: This involves cutting larger branches and requires you to have a branch cutter (a sharp pair of secateurs will do). Pruning will differ based on species, although wounds heal better in summer. Prune only once a year. Don't remove more than one-third of the tree's foliage in one session.
Wiring: Wiring allows you to move branches into a desired position. Wire branches at any time of the year, although branches set faster during the growing season. general rule of thumb is that you should apply wire that is roughly 1/3 the thickness of the branch you are planning to wire.
This guide may differ from the guide that you'll receive with your bonsai. This is due to some tree species having different care requirements.