Providing your bonsai tree with enough light is crucial for the tree’s health. The placement of your bonsai tree depends on species, climate, time of year, and many other factors. You first need to determine whether your tree is an indoor or an outdoor bonsai. This will affect how much light the tree needs and other necessary growing conditions. In this article, we will discuss light requirements for indoor and outdoor bonsai, how to determine whether your tree needs grow lights (artificial lights), and how to decide whether your tree needs a shade net outdoors.

Indoor Bonsai

Indoor bonsai trees are either tropical or subtropical trees. This means they need high temperatures and high humidity levels throughout the whole year. These trees can only survive outdoors in certain climates. 

Because they are grown indoors, it is often a struggle for these trees to receive enough light. Place your indoor bonsai tree directly in front of a south facing window or another window where it will receive as much light as possible. During the summer, many of these trees can be placed outside for a few hours during the day, but there are some trees that should not receive direct sunlight. 

Artificial lighting is often required for these trees to thrive. We will be talking more about grow lights a bit further down in this article.

Outdoor Bonsai

Outdoor bonsai trees are trees that need to be exposed to the seasons and experience dormancy periods in the winter. During these periods, it is perfectly natural for the tree to stop growing and not be exposed to high temperatures or excessive light. 

Each tree species likes a different amount of light and prefers different climates. Trees that like full sun, like juniper species, will not be happy in maritime climates. Imported Japanese species grow best in temperate climates, along with subtropical and mediterranean trees. 

If your tree likes shade and does not like afternoon sun, place it in a position where it will receive good morning light and afternoon shade.

Grow Lights

Many indoor species need artificial lighting, even if they are placed in the perfect position indoors. Sometimes sunlight through a window just isn’t enough. If your tree is showing signs of not receiving enough light, such as weak leaves falling off the tree, it may be time to invest in a grow light.

Grow lights can be used for around 10 hours a day to help your tree thrive. You can also mimic the changing of the seasons by leaving the light on for around four hours a day in the winter and longer in the summer. There are also smart grow lamps that will mimic the changing of the seasons automatically.

Shading Nets

Many trees like to be in partial shade, but there may not be areas of your yard or balcony that will suit your tree. In many particularly hot areas, shade nets may be used to protect against potential sun damage. Shading nets allow your tree to receive light while protecting it from harmful direct sunlight.

Shade nets are graded on how much light is allowed to infiltrate. Nets range from 40% to 80%: 40% nets are generally used for lower temperatures, and 80% nets are used for desert climates. For temperatures in the upper 80’s to low 90’s (in Fahrenheit), use 40%. For hotter climates in the 90 to 100 degrees Fahrenheit, 60% range is recommended. Finally, for desert climates above 100 degrees Fahrenheit, we recommend using the 80% range. 

Each net will lower the temperatures underneath it by about 10 degrees Fahrenheit.  

While bonsai trees are all very different, there are some general guidelines and suggestions when dealing with how much light they will need. When growing your tree in the proper climate, you shouldn’t have to worry about whether or not it is receiving enough light. If the sun’s direct light is too much for your trees, consider moving them to a shady spot in your yard or balcony or adding shade nets above the trees. Indoor bonsai trees are different. Even if indoor trees are placed correctly, it is still likely that they aren’t getting enough light. Adding growing lights (artificial lights) should help significantly. You should be able to tell if your tree is receiving enough light – it will be thriving!