Can Bonsai Trees Grow Big?

I’m sitting here thinking, why are bonsai trees so small and can they even grow bigger? A quick search revealed the answer, and some other interesting information.

Can a bonsai tree grow big? Yes, they definitely can. A bonsai tree is kept small by its owner. If you do not prune your bonsai and provide it with enough light, space and food, it will grow to be just as big as other trees of its species.

This has to do with the fact that bonsai is not a type of tree, but rather a style of the tree. But how easily will your bonsai become a big tree? And how can you best prevent it?

Let a bonsai grow freely without limitations

To understand why a bonsai can become big, I guess we first need to understand why a bonsai stays so small. The one and only reason why bonsai trees are miniature trees is because they are kept small by their owner.

A bonsai tree is not a special kind of tree, it says more about the way a tree is styled.

To keep a bonsai small, the owner regularly prunes the leaves and branches, as well as the roots. Because a bonsai stands in a pot and the roots are pruned, a bonsai grows slowly.

A slow growing tree, together with wires to style each individual branch of the tree results in a miniature tree that looks as close to a scaled down tree as possible.

Now if you stop pruning the branches and leaves, the bonsai tree will grow bigger! If you combine this with giving the roots all the space they need to grow as big as they want, your tree will grow to be just as big as any other tree of that species.

This means that if you for example have an Acer Palmatum bonsai tree that you bought, and you plant it in your garden, it will act like a sapling and will grow to be 10 meters tall! This is obviously only when you provide it with the right care.

Different sizes in bonsai

Next to letting your bonsai tree grow loose without any limitations (basically ruining the goal of keeping its looks like a miniature tree), you can also style the tree to be a bigger bonsai.

There are different styles of bonsai related to their overall size. This can range from tiny bonsai that you can keep in the palm of your hand up until massive trees in pots where you need 4 men to move them.

On wikipedia I found this convenient overview of all the different sizes in bonsai and their respective names.

Large bonsai

Common name	Size class	Tree height
Imperial bonsai	Eight-handed	152–203 cm (60–80 in)
Hachi-uye	Six-handed	102–152 cm (40–60 in)
Dai	Four-handed	76–122 cm (30–48 in)
Omono	Four-handed	76–122 cm (30–48 in)

Medium-size bonsai

Common name	Size class	Tree height
Chiu	Two-handed	41–91 cm (16–36 in)
Chumono	Two-handed	41–91 cm (16–36 in)
Katade-mochi	One-handed	25–46 cm (10–18 in)

Miniature bonsai

Common name	Size class	Tree height
Komono	One-handed	15–25 cm (6–10 in)
Shohin	One-handed	13–20 cm (5–8 in)
Mame	Palm size	5–15 cm (2–6 in)
Shito	Fingertip size	5–10 cm (2–4 in)
Keshitsubo	Poppy-seed size	3–8 cm (1–3 in)

With this information we now can conclude that a bonsai tree does not have to be a small tree, it only has to be a miniature version that resembles their full grown tree look. This can also be a tree that is over 1,5 meter (60 inches) tall.

Generally, people that have accumulated a lot of experience in growing and caring for bonsai trees have a preferred size. I can not call myself extremely experienced, but I love the shohin bonsai, which to me looks like the perfect bonsai.

Ways to keep a bonsai small

If you leave a bonsai tree to do its thing for an extended period of time, a bonsai tree will grow big. When you are taking care of your own bonsai this might not be something you would want to happen. So how can you keep your bonsai tree small (or at least the desired size).

To do this, you should find the right combination between pruning the leaves and branches of the tree and pruning the roots of the tree. Depending on the size and type of your bonsai tree, you have to prune the branches about once a year. This is the same for pruning the roots of your tree.

Root pruning

What effect will pruning the roots of your bonsai have on the tree?

It will mostly reduce the speed at which your tree grows, and the growth will be more compact. This will be most noticeable when you try to convert a tree or shrub into a bonsai tree. The new growth that grows on a tree with a big root structure will be long, without many nodes in between.

So by pruning the roots, you will get the nice and compact growth that is desired to add a lot of detail to your tree. Because there are many nodes close to each other on the new growth, you can shape the tree to have many side branches.

Note that pruning is also quite important in aquariums, if you want to keep your plants healthy.

Branch pruning

Pruning the branches of the bonsai is the most effective way to make your bonsai smaller in size. If you are gaining experience in pruning your bonsai, you will know how careful you have to choose what branches you will remove and where you will cut them.

In my opinion, this is one of the most satisfying and relaxing parts of the bonsai hobby. Choosing how you are going to shape your tree and trying to see years ahead to plan a tree’s look.

Growing your bonsai bigger

If you want to grow your bonsai to be bigger, but still remain a bonsai shape, there are several ways.

The first thing you should know is that your bonsai can not look perfect all the time. Growing your tree requires to grow out the branches. This means that you can not prune the branches for a longer period of time.

A good way to go is to let your bonsai tree grow for a year or even two, without interfering. Than, you can can start styling your bonsai.

Another way to go is to keep pruning and styling your bonsai, but aim for just a slightly bigger tree. This means slower growth progress but not allowing your tree to grow wild.

If you start your bonsai from a seed, or as a sapling of just a couple of years old, an option is to grow the tree in a garden for a couple of years. This will kick start the plant as a bonsai, because the trunk will thicken when there is a lot of branches attached to it. You can cut the plant to the desired size once you feel the tree is ready to be shaped into a bonsai.

At the end of the day nurturing a bonsai involves a lot of trial and error.

Bonsai Tutor