All Bonsai trees can grow outdoors and thrive when doing so if properly taken care of. There are a few types of Bonsai trees, however that better maintained where they can have some artificial source of warmth. These Bonsai don’t do well in cooler temperatures and thus should be an indoor tree. Not enough warmth and these trees could wilt quickly.
The view most people get of Bonsai plants is that they are basically an indoor plant. The media has portrayed Bonsai plants as such.
In their homeland, Japan Bonsai trees are kept outside most of the time with the miniature plants spending only one or two days inside. While inside they are generally a part of a “tokoname” display. After a few days however, the trees are returned to the outdoors because they need the time to breathe.
There are Bonsai that are used to a warmer climate and they are not grown inside for any time at all for two reasons. First off, according to Bonsai experts, all deciduous and coniferous trees require a dormancy period. This simply means that they need time to rest between growth periods. The right environment for this dormancy period is in lower temperatures.
If the temperatures are too warm Bonsai trees continue for up to two years before entering a dormancy period. If a Bonsai tree is forced into dormancy it can kill it.
The second reason these trees are not raised indoors is that it is hard to set up the right growing conditions for an indoor tree. The light has to be right and the humidity level has to be right.
Tropical bonsai trees require temperatures above10-15 degrees. This, of course, actually varies depending on the bonsai tree species. Due to cooler temperatures in some areas of the United States tropical bonsai can be outdoors for two to months out of the summer, however for the rest of the year they have to be kept indoors or they will die.
Indoor Bonsai trees will need to be close to an east, west or south window for the light. If you don’t have a window that provides light in these areas the tree will have to be exposed to artificial light. As for humidity, which is important for a bonsai tree, a small tray with gravel and water under the tree will help. An indoor bonsai tree does not necessarily need to be watered every day but make sure to check it since they tend to dry out quickly.
Make no mistake, owning an indoor Bonsai is going to take some work and care. These are not your typical house plants.