Taking care of a Bonsai tree is very rewarding and enables you to enjoy and appreciate owning a healthy bonsai tree for many years. Bonsai care is time well spent.
Temperature
Why is temperature important for bonsai?
During winter months it is vital that you keep your new indoor bonsai warm -- Not hot -- but warm, somewhere between 50 and 70 degrees Fahrenheit. Where your bonsai falls on this guideline depends on where your bonsai is from "originally" and by this I mean where in the world your bonsai is indigenous... the warmer the native climate, the warmer the area in your home it should be located.
How can temperature be monitored?
The thermostat on the wall is a good place to start. However, a small thermometer can better monitor the actual temperature of the location where the bonsai tree is located in. Most garden centres will have small thermometers available for a reasonable price and purchasing a couple is a worthwhile investment, especially if your indoor bonsai are located in a couple different areas of your home.
What is helpful to avoid temperature fluctuation?
Doors, windows, fans, heating systems and draughty hallways will all affect the actual temperature of a particular area. It is important for the health of your bonsai to be maintained at stable temperature. A sudden drop in temperature, as well as, a sudden spike in temperature can injure your indoor bonsai trees. Indoor bonsai should not be kept near a door that is frequently opened during winter months to avoid harmful cold drafts. It is important that you read the care guide that comes with your bonsai to help establish the best environment to maintain a healthy and thriving bonsai.
Air Circulation
Why is air circulation important for a bonsai?
A location with adequate air circulation is very important for the long-term health of your new bonsai. The life sustaining process of photosynthesis requires an unrestricted exchange of fresh air and stagnate environmental conditions could compromise your bonsai's ability to continue its photosynthetic processes, by clogging the pores or stomata, located on the bottom of leaves, which bonsai trees use for this vital air exchange, through dust and debris accumulation.
What else is air circulation responsible for?
A closed or confined space is the perfect environment for pests and disease, two of the most terrible enemies of bonsai trees. The regular movement of fresh air helps prevent pests, like spider mites, from establishing their webs and infesting and damaging your bonsai trees. Air circulation also assists your trees in the transportation of essential fluids from the roots to the leaves, by osmosis, which is a vital process. Air also prevents possible root rot conditions, from soil saturation, by assisting in water evaporation.
How can air circulation be improved for a bonsai?
If your bonsai is kept indoors or inside a greenhouse, you might consider leaving a door open, or cracked, and a fan, or fans, running. Spraying and misting your bonsai off regularly will help to remove all dust and debris from the bottoms and tops of leaves, allowing your bonsai to "breathe" freely and to continue its photosynthetic processes.
Pests and Disease
How can I prevent pests & disease?
When working to prevent the possible injury or death of your beloved bonsai, the best defence is a strong offence. Put simply – do the obvious - keep your bonsai clean, dust and debris free and cleared of fallen leaves and flowers. Ensure there is sufficient lighting as well as good ventilation and lots of fresh air. A healthy bonsai tree is without a doubt the most important preventative of pests and disease.
How can I treat pests & disease?
Unfortunately, even the best cared for bonsai can come across some type of pests or disease over the months and years. The first thing to try to change is your bonsai's current environment. This technique is the simplest and safest. Quite often a change of location can help an struggling bonsai tree and if it does not, at the very least, you know that your bonsai's problem is probably not environmental.
The second incremental step would be to try, if possible, to introduce biological controls such as ladybugs. Ladybugs are of no danger to your bonsai and they will eat nearly all pests that are. Of course, this technique is limited to outdoor locations.
The third incremental step would be to use chemicals, also in levels of increasing toxicity. To start, you can try spraying a very mild solution of warm water and liquid dish soap on your trees. This technique is an excellent way to prevent a wide variety of diseases and helps in discouraging many types of pests. Multiple applications may be required to achieve and maintain a healthy bonsai, but the rewards will far out-weigh the efforts.
The fourth incremental step would be to try using a mild insecticidal soap. This multi-purpose soap derivative offers effective control over most pests. This type of insecticide is one of the mildest and safest, for humans, animals and bonsai - something of a vital importance, especially if you have children and pets.
The incremental step of "last resort" would be to use an actual "chemical" spray – i.e. an insecticide. It should be handled carefully and used as per manufacturer's instructions.
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