Bonsai FAQ

Got a question about bonsai? Chances are others have had it too. Here are some of the most common ones we get asked..

What is a bonsai?

Bonsai is a Japanese term that literally means “tree in pot”. Over the centuries the term has defined an artform focussed on creating miniature representations of mature trees in nature.

How do you make a bonsai?

Bonsai are created either by cultivating a young tree or shrub into a styled plant or through collection (digging) of older plants and redesigning the specimen (known as “Yamadori” in Japanese) into a bonsai. Ensure you obtain permission first if you plan on collecting specimens from private or public property.

Can any tree species be used for bonsai?

A wide variety of trees and shrubs can be turned into a bonsai. Species that make good bonsai are perennial, have woody stems and branches and can be cultivated to stay small through pot confinement, root pruning and branch pruning. Species with small flowers, leaves or needles are often used in bonsai so that the foliage is in proportion to the overall dimensions of the tree. 

Why do bonsai trees stay so small?

Bonsai stay small due to continual root and crown pruning. Root pruning is typically done during repotting (about every 2 years), while pruning of leaves and branches is more frequent. Bonsai are NOT small due to poor tree health or because they are dwarf varieties. Well maintained bonsai are very healthy trees that would turn back into full sized trees if you took them out of the pot and planted them back in the ground.

How should I water my bonsai?

Properly watering a bonsai should include saturating the root ball, to encourage deep rather than surface root growth. For small to medium size bonsai use a watering can or hose (adjusting the nozzle to create a soft spray), moving it in a back and forth motion. You can also submerse your bonsai in water to just  below the top of the soil (so that the top dressing and soil doesn’t float away).

When should I water my bonsai?

As a rule, you should water your bonsai when the top layer of soil has dried out. The frequency of watering depends on the weather and temperature. Water more during warmer periods and less during cooler and/or wetter ones. The more exposed a bonsai is to the elements, the more frequently a bonsai should be watered.

How do I look after my bonsai in summer?

They key is to be vigilant to prevent your bonsai’s leaves from burning or the soil drying out. Different tree species have different sun and water requirements, but in general make sure to water it frequently and protect your bonsai from fully exposed positions. You also need to have a plan for when you go on holiday. This may be an automatic watering system or taking your bonsai collection to someone who can look after it for you. Chojo provides a bonsai sitting service for this purpose (see Our Services page).

When should I consult a bonsai professional?

Most people tend to come back to us when their trees seem unhealthy or over grown. It can be helpful to consult a professional once a year for assistance with long-term design and styling, which typically includes wiring and pruning.

When should I repot my bonsai?

A bonsai should be repotted when it becomes pot bound (i.e. the roots take up most of the pot). Typically, repotting should occur approximately every two years, though it depends on the speed at which your tree is growing. Repotting in an appropriate season is essential. For most species this is late winter or early spring. Subtropical and Australian native species should typically be repotted during summer.

When should I prune my bonsai?

Pruning should occur frequently through the growing season (spring and summer) to maintain the shape and silhouette of the tree. This is referred to as soft pruning. You should also give the tree a ‘hard’ prune once in the winter to refine the basic branch structure of the bonsai.

Why do we use wire to shape bonsai trees?

Wire is used to bend the trunk line or branches of a bonsai in order to give the tree the desired appearance. Typical bonsai styles mimic how mature trees appear in nature. For instance this could be a formal upright style, a windswept look (that you might see on a mountain top or cliff face) or a cascading branch structure (like trees found on banks of rivers and lakes).

When and how should I remove the wire from my bonsai?

The wire that is being used to shape your bonsai should be removed once it becomes overly tight around the branch or trunk (i.e. before it damages the tree by cutting into the bark) and/or when the branch or trunk has hardened off and is set in position. As a guide, this often occurs within 12 – 18 months from the time the wire was initially applied. The wire should be removed by cutting it into small pieces rather than unwinding the wire. This avoids damaging branches and leaves during the wire removal process.

Can I keep my bonsai indoors?

Any bonsai can be displayed indoors for short periods of time (2-3 days) however the majority of trees but must be “grown” outdoors. Some tropical and subtropical bonsai species can remain permanently indoors if they get reasonable light and ventilation.

What is a good position for a bonsai?

Most bonsai prefer some direct light through the day. Decks, patios, balconies and gardens can all be possible places to grow a bonsai. Morning and mid-day sun is ideal but not essential. Avoid direct sunlight on hot summer afternoons. Some tropical and subtropical bonsai species are able to be grown indoors (as discussed above).

Should I fertilise my bonsai?

Yes. Bonsai, like all plants, require nutrients to be healthy. The easiest way to fertilise a bonsai is by applying a slow release fertiliser (which often comes in pellets or balls), and/or by applying the recommended concentration of a liquid fertiliser on a fortnightly basis. You should avoid methods of fertilising where it is difficult to control the fertilser’s strength and dosage.