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How Big Do Bonsai Trees Get and How to Care for Them?

Japanese Bonsai trees are famous for their impressive small size and the maintained proportion similar to full-sized trees.

Plants are wonders of nature. Different plants are the different miracles, and the Bonsai tree is one of them.

The word “Bonsai” refers to the Japanese art of cultivating and growing beautiful small trees that look like giant ones. This tradition has been carried out for thousands of years.

These trees look fantastic and are very easy to care for. They appear as some dwarf trees, but they are not grown genetically. Today, in this article, we’ll see how big do Bonsai trees get and how to care for them.

A Bonsai tree under sunlight. - How big do Bonsai trees get?
“How Big Do Bonsai Trees Get?” — A Bonsai Tree under Sunlight via Pixabay.

We will primarily discuss how big do Bonsai trees get and what age they can reach up to. But on top of that, we’ll take a brief look at their appearance and how to adjust their size according to your own needs.

Furthermore, we will go through how to grow and take care of Bonsai trees.

So, without further ado, let’s get straight into the topic.

How Big Do Bonsai Trees Get?

First of all, answering the question, “How big do Bonsai trees get?”

Bonsai trees usually achieve a size between 2.5 to 203 centimeters — most giant Bonsai fall nearly 170cm, almost equal to the average man’s height.

If your Bonsai grows bigger than 203cm, it is no longer classified into the Bonsai group. It then falls under the category of small trees.

Similarly, unlike the roots of other trees that can reach up to 16 ft. in length, the roots in Bonsai tress only go up to 4 ft. in length.

Growing Bonsai often take years if appropriately cared for, but if not, it may take decades of endurance, hard work, and trimming.

Bonsai tree size usually depends on the class in which they are divided. Different size classification of Bonsai tells us how big do Bonsai trees get?

Size Classification of Bonsai Trees

The size classification of these trees is the most common and interesting fact about this plant which guides us on how big do Bonsai trees get.

Bonsais are considered small trees, but they are found in various sizes. The largest one grows in the Japanese Imperial Palace and requires four men to move.

The Japanese word “Bonsai” literally means “Potted trees.” Therefore, most Bonsai trees are grown in pots and trays.

The classification of Bonsai size is usually done by how many hands are required to move it.

Bonsai trees are grouped into different heights and have a unique name because of their size and features.

Size Classification of Bonsai Trees. - How big do Bonsai trees get?
“How Big do Bonsai Trees Get?” — Image via Javadoplant Holland.

The most miniature Bonsai trees are Shito and Keshi-tsubu, ranging around 2.5cm.

The large ones are regarded as Imperial Bonsai, after the Japanese large Bonsai trees of the Imperial Palace, and usually require eight hands to move. Over time, depending on the region, other names for Bonsai trees have been used and changed altogether.

The size classification of Bonsai started centuries ago; modern strategies may vary reliant on the region. The most commonly accepted sizes are listed below.

  • Miniature Bonsai trees: tree size is between 1 to 8 inches under this category.
  • Medium Bonsai trees: the tree size vary from 10 to 36 inches in height.
  • Large Bonsai trees: the height level is between 30 to 80 inches in the large bonsai class.

Age of Bonsai Trees

If you take care of your Bonsai, it can live for centuries. Some of the old Bonsai trees are between 500–800 years old and still live worldwide.

The oldest Bonsai tree is Ficus Bonsai in Parabiago, Italy, and is over a thousand-year of age!

You can tell the age of a Bonsai by cutting it and observing the rings inside the stem’s core. However, it is a terrific method, so it’s better to try another way to tell its age.

You can also get the estimated age of Bonsai by multiplying the diameter of the tree by its growth factor. It is important to date a Bonsai tree because old ones are often rare and highly prized.

Rare Bonsai, which gets over 800 years of age, may sell for millions of dollars.

Ways to Keep a Bonsai Tree Small

If you leave your Bonsai tree for a long time, it will definitely grow big. After knowing how big do Bonsai trees get, you may want to keep yours a little small.

That’s why growing Bonsai is regarded as ancient art — the art of the Japanese masters.

Taking care of Bonsai might not be enough to retain its growth. Then, how can you keep your Bonsai tree small? How to grow these tiny babies off of, otherwise, gigantic trees.

Well, you must find the best combination between pruning the foliage and pruning the roots. You have to prune the stems and roots at least once a year. But generally, it depends upon the size of your Bonsai.

Branch Pruning

Branch pruning is an effective way to prevent your Bonsai from growing bigger. It is an efficient way to keep your Bonsai small.

Branch pruning should be done at emerging growth and the existing limbs. If you see some awful branches, you can prune them because of their unattractive appearance.

If you are getting experience in pruning your Bonsai, you will know how careful you have to choose what branches you have to cut and from where you have to remove them.

It is undoubtedly the best and the most satisfying and relaxing part of the Bonsai hobby.

Root Pruning

Pruning roots is a normal process to help your Bonsai grow healthier.

In this process, you have to remove the Bonsai from the pot and comb out its root with a root hook. Keep younger roots and remove thick ones.

By pruning roots, you will get tremendous growth that is desired to add many details to your Bonsai tree. You can shape the tree with many side branches because there are numerous new nodes adjacent to the new growth.

Root pruning is necessary to minimize the damage to the root system during the preparation of transplantation of a large tree and also helps to maintain the size of the Bonsai tree.

How to Prune a Chinese Elm Bonsai Tree EASY!!! – Peter Chan – YouTube

Do Bonsai Trees Stay Small?

As long as the Bonsai tree remains in the small pot or container, is regularly pruned, and gets sufficient water and light, it will stay small.

The biggest reason behind the art of these miniature versions of full-grown trees is that the container restricts their growth.

Also, tree growth may have stopped if Bonsai has health issues because of inadequate watering, too much light, and fungi.

How to Grow Your Bonsai Bigger?

Most of us want to know how to grow our Bonsai bigger or how big do Bonsai trees get if left uninterrupted.

You already got the answer to How big do Bonsai trees get? Now, let’s see how to grow them bigger.

There are several ways you can try to make your Bonsai look bigger and still maintain its iconic shape.

First of all, you need to know that your Bonsai — if you desire to grow them big — won’t look perfect all the time.

Growing Bonsai trees can require long branches, so you won’t prune them for a long time. To grow your Bonsai bigger, leave it for a year or two without interference, and you can style it after that.

Also, patience, amount of light, re-potting, and soil composition are vital in growing your Bonsai bigger. Preventing your plant from fungal diseases and pest infestations also helps better plant growth.

Let’s discuss all of them in detail.

Patience

As Jean Jacques said:

“Patience is bitter, but its fruit is sweet.”

Patience is very beneficial in the case of Bonsai to grow it to the imperial size.

It will take up to 10-15 years for your Bonsai to develop into a big or medium-sized tree, while on the other hand, gigantic eight-handed Bonsai may take up to 30-40 years.

To boost the growth process, consider buying the Bonsai, which is already 20 or 30 years old, and give it time to grow.

Re-potting

The other important factor after the patience is re-potting your Bonsai consistently.

Re-potting is like restoring the life of a tree and giving your plant a better chance to live longer and grow bigger.

Re-potting needs to be done because roots are stifled in a small space as they grow. Re-potting it in a giant tray or garden is best to speed up its growth.

You will read the basics of re-potting further in the article.

Soil Composition

Soil composition plays a vital role in the growth of Bonsai trees. If you are serious about your Bonsai, garden soil may not suit your tree. You need soil that drains well and does not remain wet.

If your soil holds too much water or behaves inversely, it affects the tree negatively. As most Bonsai remain in small pots, they get limited nutrients.

So, the best option would be investing in a decent soil mix for Bonsai or making your own potting mix according to your plant’s needs.

Sunlight

Another essential aspect of growing a large Bonsai is to ensure that it gets enough light.

During the brightest month, almost all Bonsai species need light for around 4 to 8 hours a day.

So, it is better to keep your large Bonsai outdoors as much as possible, as it is challenging for imperial Bonsai to grow indoors. However, small Bonsai can generally live in an indoor environment.

An excellent option to continue the growth during the winter season is winterizing your Bonsai using a cold frame/blanket. Also, it would be better to invest in UV light to aid the development during winter.

Avoiding Pests and Fungal Problems

Sooner or later, all Bonsai owners have to face these problems.

Fungal infection proves to be a silent killer in the case of Bonsai trees. They are usually found with white spots on leaves which badly affect the plant. If you found your Bonsai affected by fungus, take it away from other plants to prevent them from the disease.

Remove the affected area and spray a fungicide to prevent any further damage.

Neem oil proves to be beneficial for a Bonsai in case of fungus. After spraying with neem oil, put the tree into a shady area for a couple of weeks or try to sprinkle in cooler months for better results.

Also, try to sterilize your tools before pruning to prevent further harm.

On the other hand, some pests like spider mites, aphids, and whiteflies attack different types of Bonsai. These can suck your tree’s life and may cause stunted growth.

You can quickly eliminate these harmful pests using suitable homemade insecticides or neem oil mixed with water. Regular check-ups for insect signs will also help to evade this problem.

Bonsai Development (2020) GET BIGGER THICKER TREES – YouTube

How To Take Care of Bonsai Trees?

Maintenance and care are a vital part of raising a Bonsai tree. Every specie has specific guidelines for care. Some essential tips for the care of Bonsai are as follows:

Watering

The amount and regularity of watering the Bonsai depend on pot size, weather, and soil. But because Bonsai is usually planted in small pots or trays, they tend to dry up quickly.

So, when you determine that soil is slightly dry and needs water, make sure to water it swiftly. Water it continuously till the water runs out of water drainage holes.

Do not overwater your Bonsai, and try to water when needed because too much watering can cause root rot, the leading cause of death for the Bonsai.

>>>Related Article: What Does Root Rot Look Like? Symptoms, Causes & Treatment.

Re-potting

The basics of re-potting are:

  • Choose suitable soil for Bonsai and re-pot your tree consistently. It helps to keep your plant healthy.
  • Most fast-growing Bonsai need to be re-potted every year or two to prevent the plant from being pot-bounded, making it difficult to absorb and retain water. But a mature tree needs to be re-potted after 3 to 4 years.

If you see the roots spinning around the root system, your Bonsai needs to be re-potted. The best way to re-pot the Bonsai is in the early spring when the plant is still dormant, and the buds start swelling.

Placement

Placing your outdoor plant indoors or indoor plant outdoor is a definite way to kill your plant if there is a massive disparity between the conditions. It would be best to decide where to put the tree before purchasing.

Small Bonsai trees are usually like indoors; they would only be acceptable to grow outdoors if you live in an area with enough warm climate. However, large ones need to be planted outdoors to get sufficient sunlight.

Fertilization

Fertilization is another essential thing to keep in mind besides re-potting and watering.

Fertilizing the tree regularly during the growing season is the key to making the Bonsai tree healthy and lavish.

Also, the amount of fertilizer depends upon your plant’s specie. Bonsai needs less fertilizer to grow rather than typical plants require.

Therefore, simply use a well-balanced liquid fertilizer diluted to 1/4th strength every month.

Taking Care of Bonsai According to its Size

Bonsai are usually cared for according to their size. The gardener determines the Bonsai size and provides the tree with suitable conditions.

You have to choose the most appropriate size while selecting a Bonsai for your landscape. The size of the tree will determine how to water and care for your tree.

Care for Miniature Bonsai

Growing a miniature Bonsai tree is challenging for Gardner because it seems more complex to grow small Bonsai than the larger ones.

Well, that’s the whole concept behind Bonsai.

Although tiny Bonsai are difficult to grow, many gardeners still aim to grow them. You can effortlessly grow a miniature Bonsai if you live in an apartment or a small space, as it won’t cover a lot of area.

  • As a Bonsai lives in small pots, it is essential to provide it with a definite proportion of water, soil, and fertilizer.
  • A small Bonsai will die if it gets over or underwatered.
  • They also need to be planted in soil with good drainage in a sand mixture.
  • Do not use complicated designs while shaping a miniature Bonsai because it generally works in the case of large Bonsai.
  • For small Bonsai, it is better to keep it simple.
  • It is considered the most time-consuming and challenging Bonsai and requires the intense attention of the gardener.
A Bonsai tree in hand. - How big do Bonsai trees get?
“How Big do Bonsai Trees Get?” — Image via Gerd Altmann.

Care for Medium-Sized Bonsai

Many people start with the medium-sized Bonsai because medium trees require regular maintenance and care. Medium-sized Bonsai are great for indoors because they are relatively easy to move around.

Care for medium-sized Bonsai is pretty much the same as miniature ones. Medium Bonsai need suitable soil to hold a little more water. The medium tree also requires sufficient fertilizer for healthy growth.

Medium-sized Bonsai allows you to choose simple as well as some complicated designs.

Care for Large Bonsai

You’ll need to go the extra mile while growing large Bonsai because you know how big do Bonsai trees get and that they can have limited flexibility, but developing a large Bonsai is much easier than miniatures.

  • Large Bonsai trees are usually planted outdoors because they get adequate sunlight there.
  • They are also cumbersome and need multiple people to be lifted, so they don’t typically move enough.
  • Like other sizes, large Bonsai also require suitable soil and sunlight.
  • The ground must have good drainage and ventilation.
  • Some gardeners install an automated water system for their Bonsai to ensure the tree does not dry out during the hot day.
  • Large Bonsai trees look best with complicated designs due to their imperial size.

Conclusion

This introductory article covers all the significant aspects of the Bonsai tree. How big do Bonsai trees get, their shape, size, and care for a Bonsai tree… Answering all these questions, let us conclude the talk here.

It all depends upon the gardener to decide the size of the Bonsai tree.

In ancient Japan, the size classification was determined by how many hands were required to move it. Size classification helps the gardener better understand the plant and helps in caring for Bonsai.

Furthermore, if you want to keep your Bonsai small, then prune it often from roots and branches.

But if you want a giant Bonsai, then patience and other factors mentioned above would help you through the journey.

No matter which size you wish for your Bonsai, you have to give proper care and affection to your plant to make it live a healthy and happy long life.

Regards,
Moiz Atiq.