Bonsai – Air, Humidity, and Temperature
Like any other plant, fresh air and adequate humidity are essential for small trees. In fact, both these elements are very important even for people as well as wooden furniture. It is not a problem to provide the plants with both during summers, as they can be taken outdoors to a balcony, terrace or even the garden, where there is plenty of fresh air and humidity. The only thing you need to ensure is that the small plants have enough time to gradually adjust to the air, light and sun outdoors. Therefore, the best thing to do is to bring them outdoors step by step. To begin with, you can put them outside for some hours on rather cloudy days during the beginning of spring at a time when the sun is yet to reach its full intensity as in the summer months. So you can place your bonsai trees indoors or outdoors subject to the weather conditions.
It is just the opposite during the winter months, when we need to switch on the heating system to help the bonsai trees. In fact, humidity around 40 percent to 50 percent is ideal for the trees around this time of the year. In case you do not have a preference for electric humidifiers, you may place any pottery tray full with water close to the bonsai tree or you can place it on the heat registers. In any case, doing this is also helpful for the respiratory passages in humans.
There is another means by which you can provide the needed humidity to your bonsai trees. All you need to do is place the trees on any tray packed with gravel or sand. You need to ensure that the gravel or sand in the tray should always be damp. This type of set up is especially suitable for plants that are placed on a windowsill having a radiator or a heat register below.
Humid air is vital for bonsai trees as it reduces the loss of water via transpiration. In fact, when the days are very dry, the roots of the trees may take up much less water than what is needed by the bonsai plants. In case, the bonsai loses excessive water, the stomates found on the leaves’ underside close up; the exchange of gases necessary for photosynthesis is suspended, and even the growth process of the tree is disrupted. This also occurs when the stomates are blocked due to dust accumulation. This is the reason why it is advisable that you give your bonsai trees a moderate shower in a bathtub at least once every month.
While purchasing a bonsai tree, always remember that your house may become particularly arid during the winter months and may be even somewhat covered in dust. However, all this will depend on the type as well as amount of insulation being applied. Hence, be careful and judicious while choosing the right bonsai. A number of bonsai trees are more susceptible compared to others to arid conditions. It has been observed that bonsai trees having rather leathery leaves do not give up moisture as easily as others and are more suited for growing in indoor conditions having low levels of humidity. The Ficus buxifolia is a wonderful example of bonsai plants requiring high levels of humidity. This plant bears large and soft leaves that are an indication of the fact that there is a lot of transpiration taking place. As a result, this plant needs to be placed in an area where there is high humidity. Another example of such bonsai plants is Lantana. This is one of the main reasons why any grower having indoor plants ought to also have a hygrometer to measure the water vapour present in the atmosphere at regular intervals.
Bonsai growers in several regions should bear another important aspect in mind – drafts during the winter months. In fact, tropical plants are very vulnerable to drafts. Precisely speaking, the risk of opening the windows, even slightly or for a moment, becomes more risky with further drop in the temperature outside. Therefore, bonsai gardeners recommend that when it is very cold outside, you should remove your plants from the windowsill before you open the widows even slightly. On the other hand, bonsai growers who do not have the opportunity to take their plants outdoors during the summer months can actually air out their house very frequently.
While taking the requisites of your bonsai plant into account, you need to bear in mind that there is no plant that has been created for living indoors. While creating a suitable environment indoors for your bonsai trees, you should always bear in mind the natural habitats of these plants. In fact, that should be serving as a guide to you while creating the indoor environment for the plants. This is all the more important while maintaining the right temperature for the plants. It is advisable that you should always choose your plants – tropical (heated greenhouse) or sub-tropical (cold house) species depending on what type of green island you wish to create inside your house.
In their natural environment, sub-tropical trees as well as bushes are acclimatized to warm summers as well as cool winters. When these plants are grown outdoors, they have a preference to be in an environment that is sheltered from strong winds. However, they will gradually be accustomed to the outdoor conditions.
When grown indoors, especially during the winter, these plants have a preference for cool places where a temperature ranging between 41°F and 59°F (5°C and 15°C) is considered to be ideal during the day time and a slightly lower temperature range during the night is perfect. Depending on the season as well as the prevailing weather conditions, any sensible and smart bonsai gardener will place his/ her sub-tropical bonsai plants on the terrace, on a balcony, in the hallway or in the bedroom, or even the staircase with a view to provide them with the appropriate amount of heat, light, air and humidity.
Similarly, bonsai trees created from tropical species should always be kept warm all through the year, as these plants almost continue growing without any dormant period in their natural environments. The ideal day time temperatures for these plants should range from 64°F to 75°F (18°C to 24°C), which they would be feeling comfortable when the temperature range is between 57°F and 61°F (14°C and 16°C) at night – which is actually the standard temperature ranges in several contemporary homes during the winter months.
Therefore, you can place your tropical bonsai trees directly on top of a heating source in winter and still they will not give up much moisture, provided you ensure that they receive the appropriate levels of humidity. However, you ought to know that the tropical bonsai trees loathe cold feet, which generally occurs when the region around their roots is colder compared to the adjacent atmosphere. The possibilities of cold feet become more when the windowsill in your house is made of marble or stone. This may also occur if cold air infiltrates via small cracks in the windowsill. So ensure that the tropical bonsai plants never encounter such conditions.