How to Choose the Right Pot Size for Your Bonsai Tree?

Of course, we all want to put our bonsais in beautiful pots that show off the uniqueness of our little trees. 

And you can definitely get a nice-looking container without breaking the bank, especially if you buy from a country like China. 

But, of course, price and look aren’t everything. 

So, functionally, what sort of pot do you want to get for your bonsai?

You can use almost any small container with drainage holes. 

But, you do need to think about how big you want your tree to get as well as the shape of the tree when choosing a pot. 

Overall, though, a bonsai pot needs to be small enough to restrict the tree’s growth but large enough to provide it with water and nutrients.

In this article, we’ll look at what size pot you should get and other aspects of the perfect bonsai pot. 

How Big Should a Bonsai Container Be?

Certainly, you need to think carefully about container size. 

But unfortunately, there is no hard, fixed rule that says what size a bonsai container should be.

The best rule of thumb, though, when it comes to depth is that the pot should be no deeper than the diameter of the tree’s trunk, just above the soil level.

The greatest diameter when it comes to your container is also relatively simple to figure out. 

If you have a rectangular or oval pot, the diameter should be about two-thirds of the tree’s height. 

If you have a circular pot, on the other hand, the diameter should be one-third the height of the tree.

Other factors to remember when looking for the right pot include: 

• Trees with a vast canopy may need a broader and shallower pot. 
• Bonsais with unusually thick trunks will need a deeper and narrower container. 
• Trees with fast-growing root systems and bonsais that produce fruits should have deeper pots.
• Slow-growing trees will often cope better with smaller, shallower pots because they keep their size restricted.

However, remember that these rules are only a guideline to help you find a container that is approximately suitable for the plant you wish to grow.

It’s worth noting that many people do break these rules when choosing a suitable container for their bonsai trees. 

But, it’s essential to do so consciously and intentionally, rather than “just because” you feel like it. 

You must still keep the container approximately the right size, or your bonsai will either die or outgrow its container.

Can a Bonsai Container Be too Large?

A bonsai container can undoubtedly be too large. 

If you give your tree’s roots too much space, it will grow quickly and may try to break out of the pot.

Fast growth can be harmful to the bonsai’s overall growth arc and may leave your tree struggling when you restrict its growth in the future. 

Also, if you don’t restrict the tree’s growth at all, it will soon outgrow the size of a bonsai.

Additionally, your tree could end up rootbound, forcing its roots back in over themselves, which will make it much harder for the tree to keep putting out healthy roots as it grows.

It’s also easy to end up with too much water in the lower parts of the soil with a large pot. 

And an abundance of water may cause the tree’s roots to rot because the water will stay there and cause bacterial buildup.

Large pots tend to warm up more slowly, too, resulting in slower growth because bonsai trees generally like to be warm.

Furthermore, a deep pot will have reduced airflow lower down, which isn’t ideal for the growth of the plant’s roots.

Many people think that putting their bonsai tree in a large pot is better than choosing a pot that is too small, but a large pot can be just as detrimental. 

Generally, a large pot will lead to either rotten roots or poor root growth, so you should avoid it.

Can a Bonsai Container Be too Small?

A bonsai container can indeed be too small, which will harm the tree.

Overall, a pot must have enough space to provide anchorage, water, and nutrients.

If there is no room for soil or new growth in your plant’s container, it will quickly stop growing and may even die.

Thus, you must ensure that the pot has enough space for the plant’s roots, or your bonsai will have no hope of flourishing.

Typically, if you find that water is running around the edges of the container rather than penetrating the soil, it may be time to re-pot your bonsai so that the roots have more room. 

How Much Bigger Should a Pot Be When Re-potting?

You can use a technique called slip-potting if you are keen to keep gently sizing your plant up. 

To do this, you should choose a pot that is just a little larger than your bonsai’s current container.  

But, keep in mind that this method is more work than if you choose a container that is several sizes up. 

However, the split-potting technique can be better for the tree, and many nurseries use this approach.

It keeps the root growth even and doesn’t give the tree a sudden large space to fill.

Does the Pot Have to Have Drainage Holes?

Your bonsai container must have drainage holes, as they are absolutely critical to keeping the tree healthy.

Some people think that if they plant a bonsai in a pot with no drainage holes, it will not need frequent watering, but this is not a good way to grow a bonsai.

If water stays in your plant’s pot for a long time, the plant’s roots won’t get enough oxygen, and harmful bacteria may start to grow in the soil.

This bacteria will then attack the plant’s roots and quickly kill the bonsai by making the roots rot.

Conclusion

It’s crucial to get the right size pot for your bonsai tree. 

Overall, your container must be approximately the same depth as the trunk’s diameter and no more than one-third or two-thirds of the tree’s overall height. 

There are some exceptions, but using these rules should help you determine what pot size is best for your tree.