Indoor Bonsai Plants
It is not apt to classify a bonsai plant into indoor bonsai plant and outdoor bonsai plant, since all bonsai plants show a better tendency to grow outdoors. Therefore the bonsai trees are better cultivated outside. However there are certain tropical plants, which will need some artificial source of warmth. They can’t survive low temperatures of certain periods in a year. Such plants are grown as inside bonsai plants. Otherwise they would wilt away.
Bonsai plants are often mentioned as indoor bonsai plants in magazines and books. But this is only temporary. In Japan, they are raised inside 1 or 2 days indoors at a time and are shown as part of a tokoname display. Then they are returned outside to let them recover. The temperate climate bonsai are not grown inside for any length of time for two reasons. Firstly, all deciduous and coniferous trees require a dormancy period. This is only possible in lesser temperatures. In warm temperatures, trees continue their grow for anything up to two years before entering dormancy stage. This enforced dormancy could be fatal.
Secondly, it is hard to provide the right growing conditions for indoor bonsai plant. The light level is lower, humidity level is poor and the tree suffers a lot from inadequate air circulation. For bonsai plants, hardy to frosts, it is always preferred to cultivate them outdoors throughout the year where they can grow in a healthy condition.
On the contrary, tropical bonsai plants require temperatures above around 10-15°C. This may vary depending on individual species. In cool temperate areas of US and European countries, this means that many tropical bonsai can only be kept outdoors for 2 or 3 months of the summer. For the rest part of the year, they should be cared as indoor bonsai plantsInd