4A - Frequently Asked Questions About Bonsai Trees

Posted on 9 Apr 06:42

Frequently Used Terms & Asked Questions About Bonsai Trees


Practiced for centuries in China and Japan, the art of Bonsai is the reproduction of natural tree forms in miniature.  Bonsai trees are living miniature trees which increase in beauty and value as they mature over the years.


How often should I water my bonsai tree?
Unlike a houseplant, bonsai trees use a "free draining" type of soil because their roots cannot tolerate "wet feet". In addition, they are grown in significantly less soil and, therefore require more watering.  Factors such as tree location, temperature, lighting conditions, quantity of soil used, and the changing seasons will determine the frequency of watering.
In summer, your tree could require daily or twice daily watering depending on the environments humidity and temperature. In winter watering will depend on they type of tree.  Trees in dormancy may only require weekly watering. 
Indoor trees or trees brought indoor for the winter, may only require water ever other day,  Frequency will depend on the type of tree,  temperature and humidity in its environment.
By observing your tree, you will get to know when your tree needs to be watered.  Observe the foliage; soil color; pebble color; test the soil with your finger just below the surface; test the overall weight of the pot/tree. (The drier the soil, the lighter pot/tree will feel.) 
Setting a general watering schedule, then becoming familiar with your tree; is the best way to tell when your tree needs water adjustments.
For Beginners, we recommend an inexpensive moisture meter.  Moisture Meters work very much like a thermometer. Inserted into the soil, the meter needle will tell you if it is time to water.  I highly recommend a moisture meter for beginners and people who are not used to caring for house plants.  Go To Moisture Meter


How often should I fertilize my bonsai tree?
Because bonsai trees are cultivated in limited amounts of soil, adequate feeding is very important. As a general rule, fertilize monthly during the Growing season.  Fertilize less frequently in the Fall, none at all in Winter (dormancy) and a more often in the Spring.
Feeding for bonsai should contain three principle ingredients; nitrogen, phosphoric acid, and potash. It is also a good idea to use a fertilizer containing "chelated" iron.
Water before fertilizing your tree; then apply fertilizer mixed at half the strength recommended by the brand's manufacturer.  We rotate the use of brands since different manufacturers add different amounts of trace elements and minerals. We also add Superthrive, which is a vitamin supplement, to our fertilizer mix. 
Beginners may find it easier to use slow release fertilizer granules (placed over the soil), whose nutrients are released with each watering.   Go to Fertilizer

How often should I mist my bonsai tree?
Though there are a few exceptions, almost all "wild" tree species used for Bonsai grow in more humid conditions in nature, than Bonsai Trees grow under in our homes, offices and dormitories. Thus, Bonsai Trees need you to provide this essential humidity.
Misting every week or so, depending on environment, will help cleanse the leaves, but keep in mind misting for humidity is only beneficial for a short time. 
For continual humidity, we recommend placing the tree on a humidity tray and filling the tray with water.  As the water in the tray evaporates, it creates a humid environment around the tree 24 hours a day.  When the water in the tray is gone, add more water. Providing humidity this way, is one of the reasons bonsai pots have "feet"; to hold the bottom of the pot out of the water in the drip tray.
Adding Pebbles to cover the surface of the drip tray not only decorative, but is beneficial in a couple of other ways; pebbles in the drip tray add surface area, which increases water evaporation rate; pebbles also sets the pot higher to further raise the roots from the water. Appropriate promotional humidity / drip trays are available to add to your bonsai purchase.


How much sunlight is required for my bonsai tree?
Sunlight, especially the ultra-violet ray, affects the growth of trees. Therefore, except in special cases such as immediately after re-potting, extensive trimming, etc, bonsai should be placed in a sunny location. Bright artificial light will also work well, but the tree should not be placed more than 12" away from the direct light source.
Eastern, western or southern exposures work best (in that order). A northern exposure will probably require the use of supplemental "grow lights".  Artificial lights should remain on from 12 to 16 hours each day.  The lamp should not be closer than 2 inches above the foliage of the tree.
Use of incandescent lights will hold you over until you can get grow lights.  However, specialized grow lights are recommended; incandescent light bulbs are too hot and will not provide the various spectrum of light that is required to maintain your bonsai tree. 
If you do not have a window or light source that provides an east, west or southern exposure, you should consider selecting a Bonsai Tree which does well in lower lighting conditions.

How is miniaturizing a tree possible?
No one single technique makes a tree small. Growing the tree in a container, the trimming, pruning, re-potting & root trimming, as well as other care given the tree; all contribute to the final result of limited growth.  In bonsai culture the environment is manipulated to trigger dwarfing. 
Bonsai Trees are grown in shallow containers, the size of which determines the amount of soil available to the roots. This is one of the major environmental factors used to restrict the growth of the roots and their functions; restricting the roots restricts the size of the tree.

How do I trim and prune my bonsai?
The main objectives of trimming and pruning is to shape the bonsai into the desired form and to reduce growth above ground in order to maintain a balance with root growth. The process of shaping begins when the tree is very young and is on-going as it continues its growth.
Trimming is accomplished by using a sharp scissors or shears. This traditional tool is called butterfly shears or bonsai shears and is used for removing foliage and light branches.
Pruning is the removal of heavier branches; the tool to used is the concave cutter, for which there is no substitute. The concave cutter allows you to remove small, medium and even large branches without leaving any visible scars.
Some trees such as the Juniper, should be trimmed by using the thumb and index finger to remove new growth.  This will prevent browning and a "sheared" appearance.  Go to Bonsai Tools and Accessories

How do I prevent diseases and insects from infecting my bonsai?
As living trees, bonsai are susceptible to insect attacks and disease.  Preventive and corrective measures include (a) keeping your bonsai in good health, since insects and bacteria tend to attack weak trees, (b) giving your tree ample light, fresh air and ventilation, (c) keeping the soil free of spent blooms and fallen leaves etc. You may also use an insecticidal soap spray which is not harmful to humans or animals. This soap derivative, however, may require more than one application to control the insect population. It's also a good idea to use this spray weekly to prevent any attacks.

How do I train my bonsai?
Wiring, a relatively modern method of training bonsai trunks and branches into the desired forms, has become commonly accepted. It is often used in place of, or in conjunction with the traditional methods of long-term pruning and hemp-rope binding. Copper wire that has first been annealed in a low-temperature fire is preferred. It is wrapped around the branches in the direction the branch is to be bent. The branch should be bent into its final position, taking care not to harm the cambium layer under the bark.
The wire should be wrapped taut, but not too tight, and should be removed before it bites into the branch; after between 6 and 12 months. The wire is removed with a bonsai wire cutter by snipping the wire at each turn, thereby allowing the cut pieces to fall to the ground. Never unwind the wire or use pliers to cut the wire, since this will damage the branches.  Go to Wire

What is bonsai soil and why is it used for bonsai?

As noted previously, Bonsai trees do not do well in soil that is always wet. Compared to Bonsai Soil, regular potting soil and top soil are heavy soils, which can remain wet for weeks. Bonsai soil is a mixture of ingredients which allows the water to drain freely and at the same time, retain moisture. In addition, the ingredients allow the roots to breathe and prevent compaction. There are two basic types of bonsai soil; a conifer mix and a tropical/sub/tropical mix. Before adding any soil mixture, be sure to cover the drainage hole(s) with screening to prevent the soil from washing out of the pot. When re-potting, it is always best to use the soil mixture in its dry state. Go to Soil


How often should I re-pot my bonsai tree?
All potted plants will eventually outgrow their containers. While houseplants need to be "up-potted", that is, placed in larger and larger containers, maintaining the miniaturization of a bonsai tree involves keeping the roots confined to the small container.

On average, re-potting will be necessary every 3-5 years, but the tree should be removed from its container and its root system inspected once a year.
If the roots form a circular ball around the perimeter of the pot, it is time to trim the roots and re-pot.

When re-potting remember to:
(a) use only bonsai soil
(b) remove air pockets by working the soil down through the roots
(c) do not remove more that 20% of the root system
(d) re-pot during the appropriate re-potting season

(e) water well and keep out of the sun for a week or two after re-potting.