Growing a bonsai tree can be a relaxing and rewarding art form. Juniper Bonsai trees are one of the most common bonsai but repotting a tree is a concerning aspect of growth for many beginners. It can be intimidating to repot but it is not a guessing game.
Many of us are rightfully concerned about uprooting and repotting a tree that we may have spent so much time growing.
The following tips will answer questions around repotting more in-depth and cover more aspects related to repotting a juniper bonsai.
How Often Should a Juniper Bonsai be Repotted?
For new bonsai enthusiasts, it should be understood that repotting is as important as watering, albeit much less frequent. The frequency of repotting depends on the age of the tree.
It is widely recommended that younger trees, under 10 years old, are repotted once every 1-2 years, more mature trees can wait 3-5 years.
This range of time between repottings may also be more accurately determined if we examine the tree’s roots. Distinct signs that it is time to repot are:
- Your tree is rootbound (also known as potbound). This means the roots have filled the pot. The tree has outgrown its pot and a tree that is rootbound will have a difficult time absorbing water and nutrients.
- When the tree is pulled up, the root ball comes out easily and in one clump.
- When the tree is pulled up, there seems to be a lack of soil. During its life, the tree doesn’t just live in the soil, it consumes it and will deplete the soil.
- The soil has apparently become compacted by the roots and the roots are swelling upward towards the surface.
- In addition to all of these signs in the roots, you may also notice that the overall growth of the tree seems to have slowed or halted during the previous spring and summer.
Any one of the previous indicators alone can be enough to tell you a repotting is due for your juniper bonsai, they all signal that the tree is outgrowing its pot, and the tree’s health may soon be impacted.
But what are the specifics of this procedure and why exactly is it beneficial to the tree?
Why Should a Juniper Bonsai be Repotted?
The growers’ main goals of this bonsai repotting procedure are to:
- Change or replace soil.
- Prune the tree’s roots, removing the larger, older roots.
- Comb the roots out so they are no longer all clumped together in a ball or in the shape of the pot. (This can be done by hand or with special tools.)
- Move your bonsai tree to a larger pot if needed.
Respectively, this process will promote the health of the tree in that:
- Fresh soil will replace missing nutrients which have been consumed by the tree. This will also restore the pH balance of the soil making it once again optimal for the tree to thrive.
- Older, larger roots are less efficient at absorbing water and nutrients. They also take up more room in the pot, not allowing for new root growth.
- Spreading the roots apart will increase their efficiency at absorbing water and nutrients. This will help them grow.
- As the tree grows it will require more space. By giving your bonsai a larger pot, you will promote new root growth and expansion.
You understand when the ideal time is to repot your juniper bonsai, and how often. The basic reasons for repotting and the signs that your tree is due for this procedure to have been covered so far.
But what if you’re worried that your tree’s health is deteriorating and it is not in the late winter to an early spring time frame? To better answer this question, we should define a term that was previously used.
Wait Until Dormancy Ends to Repot
Dormancy is essentially the period in which a tree is hibernating to survive seasonal conditions. This process helps the bonsai save energy and helps prepare the tree for the large amounts of energy that the spring and summer will require once the growing season begins.
By waiting for the end of dormancy to repot, you will minimize stress for the plant while ensuring that the roots you prune during the repotting process will heal quickly after the tree becomes active again.
Can You Repot A Juniper Bonsai in the Summer ?
Although summer is not the recommended time for repotting, some growers have claimed to have had luck with the procedure outside of the tree’s dormancy.
Generally, these cases involve moving the tree to a larger pot and changing or adding fresh soil. Also, it is advised by many bonsai growers that pruning of the tree’s roots is still kept to a minimum or not at all, until near the end of its winter dormancy.
If roots are pruned during the summer the tree can become stressed. This happens because large amounts of energy are already being spent by the tree during its growing season.
If the trauma of root pruning takes place on top of all the other growth it may be too much for the bonsai.
To address the other side of the seasonal spectrum, winter is not the ideal time for root pruning either but like summer, you can change the tree’s pot and add soil. Mid-winter, during the height of the tree’s dormancy, the bonsai is not growing in order to save energy for all the growth it has in the seasons to come.
The “damage” done to the roots by pruning them will not heal and this leaves the roots vulnerable to frost (depending on where you live), as well as the roots rotting.
Fertilizing After Repotting a Bonsai
For beginners, you may find yourself somewhat anxious to fertilize your Bonsai immediately after repotting. You may have the intention of helping the tree heal faster and giving it a head start. This is not recommended.
Fertilizing your bonsai too soon after repotting can have negative effects on freshly pruned roots and your good intentions may end up harming the tree. But give the tree 4-5 weeks to recover and it can be fertilized as you normally would.
Watering After Repotting a Bonsai
As for watering after repotting, some bonsai growers advise waiting a week before watering your tree, however, it is more widely suggested that you should keep the roots moist.
Do not oversaturate the freshly pruned roots with water. Too much water can lead to problems with root rot. A light watering on a consistent basis will be just fine.
Why Is Your Bonsai Tree Brittle might be an interesting article for you!
Will Repotting a Bonsai Kill It
Repotting a bonsai can be intimidating. Not only for those growers who are just starting out but even those that have been practicing for some time.
There is so much time and patience involved in growing these trees, it can be hard to wrap your head around the idea of pulling them from their pots and the soil they live in. Repotting is part of keeping the tree healthy. Your bonsai will survive many repottings during its life.
If there are any remaining concerns about when to repot just remember, As long as you do your repotting and major root pruning in the late winter or early spring, during the end of the tree’s dormancy, there is little to worry about.
Your bonsai will continue to provide you with hours of relaxation, enjoyment, and pride.