So, you just got into the exciting world of Bonsai Tree care taking and one of your friends asked you when you plan to repot for the first time.
There are plenty of articles out there about repotting a bonsai tree, but what about bonsai seedlings? Well, do not worry, as you have finally found the answers you have been looking for.
When starting to consider when to repot your bonsai seedling, the best place to start is with a better understanding of why a bonsai seedling needs repotting to begin with. Keep reading to learn when to repot your bonsai seedling and where to start in the process.
When to Repot Your Bonsai Seedling
There are a few important factors to consider when repotting a bonsai. Once you review all these factors, you will have a better idea of whether now is a good time to repot your Bonsai or if you should wait until later.
This will ensure your bonsai has a better chance of survival and limited complications arise.
- The age of your bonsai seedling
- The time of year
- The health of your bonsai’s roots
The age of your bonsai seedlings can drastically affect the time you should repot your seedlings. Additionally, the time of year, or seasonality, is also critical for ensuring that your bonsai seedling thrives after being repotted.
Aside from this, the condition of your bonsai’s roots is also crucial, as the roots can provide you tell-tell signs that you should repot your bonsai seedling.
Why Bonsai Seedlings Need to Be Repotted
To put it simply, like any living thing on the planet, as your Bonsai gets older, it will eventually need more room to “spread its roots”.
Bonsai trees come in several shapes and sizes and all have differing growth factors which affect how quickly they mature.
Bonsai such as the Japanese Black Pine, Snowdrop and Maple, as well as the Chinese juniper grow fast and as such will need more frequent repotting than their slower growing brethren.
So why do you need to repot exactly? Sure, they need more space to grow bigger but what happens if you do not repot regularly?
Well, the truth is your bonsai will stop growing completely and its roots will start to conform to the shape of the pot you chose for it initially. With this stunted root growth, comes the denial of the main plant growing any larger and its root growth coming to a halt..
The last reason why you need to repot bonsai seedlings is to ensure they do not die from starvation. Another key component of repotting is ensuring new fresh and nutrient rich soil is added to the bigger pot the seedling will be transferred to.
While these are all great reasons why you should repot your seedlings as they mature, keep in mind that once they have matured fully, the need to repot drops significantly.
How Old Is Your Bonsai?
Bonsai seedlings do age, and as they mature, the need to repot them goes down as their growth slows.
The general rule of thumb is that young bonsai seedlings should be repotted every two years while older, more matured bonsai should instead be repotted every four to five years.
Does that seem like too long of a time? You are partially right. The main thing to keep in mind is no matter how old the bonsai tree is, they remain fragile throughout their lifespan so repotting, while crucial, should never become a thing you do “just because”.
If you are unsure how old your Bonsai is, please do not cut a piece of it off to find out. The little darling will not be able to handle it.
There are a few different resources out there that explain how to calculate the age of your Bonsai tree (and others) and typically it comes down to measuring the tree’s trunk diameter and plugging that number into a calculator that will estimate your tree’s age.
Once you have that in hand though then the next thing to factor in is seasonality.
What is the Time of Year?
As most plants are wont to do, Bonsai trees go dormant in certain seasons and grow during others.
Repotting a bonsai during the incorrect season can lead to worse problems than the stunted growth that could happen should you not repot at all. With that in mind, the best time of year that most experts agree upon is either extremely late in winter or right at the beginning of spring.
In the United States, this would typically be considered the months of January, February, or early March.
Depending on your location, this may differ but whenever your region is entering actual springtime weather after a period of cold should be when you start to investigate repotting.
The reason you wait until this time is that, while the plant is dormant, it is less likely to develop issues when cut and rearranged versus when it is actively growing.
Repotting an actively growing Bonsai plant can lead to the bonsai developing disease in its roots.
Performing the transplant when it is dormant and just before growing begins, however, gives the plant more than a fighting chance as its roots can grow back right along with the changing of the seasons in its new home.
Best Types of Rocks for Bonsai Trees might be an interesting article for you.
How Are Your Bonsai’s Roots Looking?
Yep! Even after all the science and math from earlier, the most important factor when determining whether it is the right time to repot your bonsai seedling is to look at the roots themselves.
Bonsai roots, as noted above, will over time conform to the size and shape of the pot as it grows. One clear-cut sign that it is time to swap your pot is if the bonsai’s roots have formed completely around the root ball that you provided it when planting.
Should the bonsai’s roots not be formed around the ball, then it may not need transport at this time.
More factors to look out for are:
- Soil drying quickly after watering
- Roots poking out through the holes in the bottom of the pot
If the soil is drying out at an extremely fast rate, then the plant has reached a point where most, if not all of, the nutrients are gone from the soil due to the Bonsai Seedling absorbing all it can at this time.
Another factor could be if you see the Bonsai roots poking out through the holes in the bottom of your pot. If they are poking out, this means the Bonsai has outgrown its current home, and it is time for a change.
With all that said, even if the above is found to have occurred, remember you need to first confirm the time of year before you begin the transplant procedure.
By confirming the bonsai tree’s age, you can then decide if it needs more or less frequent repotting.
Once you know how often you should check for repotting, you check the current season to decide if it is safe to repot the plant or if you should wait until later. Finally, once you fulfill these previous conditions, you want to look for physically telling signs that the Bonsai is ready to move on.
Remember that repotting is an especially important part of a bonsai’s life cycle and perfecting the above will ensure that your bonsai will live a long happy life.