How not to Kill a Bonsai.

"Killed with kindness", is the most common cause of Bonsai death. 


In this post, I would like to dispel the myth of Bonsai being hard to grow. The most common mistakes new Bonsai enthusiasts make are over-caring, too much watering, repotting at the wrong time, fertilizing weak trees, etc.


To set you up for success, let's quickly discuss some common mistakes and how to avoid them. If you're not into reading too much, scroll down to the DONT'S for a quick read. 



Trees often experience stress as Bonsai forces them to deal with training, pruning and repotting. An old saying circulating in Bonsai is never exposing the tree to more than one major stressor a season. So if you are planning on doing heavy pruning and shaping in the spring, do not repot the tree in the same season. Wait until you see signs of growth and a healthy, vigorous tree before attempting any major work on the tree. After any significant work on a Bonsai, give the tree the time and care to recover before attempting any additional work. A good guideline is to follow the trees' seasonality and work within the Bonsai's natural seasonal cycles. 



Generally, trees are not too keen on moving around. In nature, once a tree plants its roots, that is where it will stay for the entirety of its existence. Regardless if you're bringing home a Bonsai or Pre-Bonsai from a nursery, forest or having it shipped, it is always a good idea to let the tree acclimate to its new environment slowly. Place the tree ideally in the location where you would like it to stay, leaving it to adjust to its new environment slowly. During this period, the only thing to do is water the tree when it needs it and check on it often to see if the location has a negative or positive effect. 

Negative signs tend to show up quicker than positive. Warnings to pay attention to are the leaves are upright, not sagging or wilting. If it seems like the leaves are stretching or reaching, that is usually a sign of not enough light, so maybe the location needs to be adjusted, or a grow light added. 

Positive signs are new growth, which may take anywhere from a few weeks to a month or two, depending on the species and environment. New bulging buds or leaves emerging are signs the tree is happy and healthy and is acclimating well. 



Always wait until the tree is healthy and showing signs of growth before attempting to repot the tree. Depending on the tree, a full repotting can should be done during specific times. For example, maples need to be repotted in early spring when new buds are bulging before the leaves emerge, and this period is the best time to repot a maple. If you would like to repot a Bonsai at any other time other than what is recommended for that species, slip potting should be the method used. 

Slip-potting is a method in which the majority of the root ball is not disturbed when repotting. To slip-pot a tree, remove the tree from its container or pot. Once removed from the pot, the roots need a little gentle teasing on the outside of the soil so that they do not circulate but rather stick out. Then with most of the soil and root ball still intact, place the tree into the new pot and fill around with the best soil mixture for that type of tree. Slip-potting can be done at almost any time of the year if the tree is healthy, happy and growing.




Bonsai require fertilizer to grow and thrive since most soils and substrates used to ensure good drainage are inorganic matter. Even when combining organic matter into the mix, it is often not enough for the year or two until the next repotting. Here, fertilizer comes into play and is an absolute must for healthy and happy trees. For trees that go dormant during the winter months, fertilizer should only be applied from spring to fall. Starting when first growth appears and gradually slowing down in mid-fall. For indoor Bonsai, fertilizer can be used year-round. During the winter months, the amount of fertilizer needs to be adjusted to half or less of the usual amount. Fertilizer is not medicine for a weak tree, and adding fertilizer to a tree already struggling will worsen the situation. 

Important - NEVER fertilize a weak or stressed tree. If any significant work like main branch pruning, root pruning, repotting or wiring has been done. Make sure the tree is showing signs of growth before applying fertilizer. 



Cheat Sheet for Keeping Bonsai happy and healthy. 



  • Do not repot your tree as soon as you get it home. 
  • Do not water your tree more than it needs.
  • Do not Fertilize your tree when you think it is not doing well. 
  • Do not attempt any significant pruning on a tree not thriving.
  • Do not try to nurse a weak tree back to health by repotting and/or fertilizing it. 
  • Do not forget to check on your tree daily in the first few weeks. 
  • Do not carry your new Bonsai with you everywhere to show all your friends and family what a gorgeous Bonsai you have. 



  • Give your tree the time to acclimate to its new environment. 
  • Monitor the soil and water it when needed based on the species. 
  • Fertilize your Bonsai when it is healthy and during the growing season. 
  • Enjoy your Bonsai, admire its beauty and elegance. 
  • Trim and prune it to maintain shape and interest. 
  • Have patience.


What is the best temperature fir a bonsai and dies it have to be constant?

Sandra Smale December 31, 2023

Thanks for all the useful information you posted on your site

Marcel O E Ladouceur March 30, 2022

The above information is very helpful, written plainly & concisely; enough to make one comfortable that caring for one’s BONZAI can be done, while enjoying the tree at the same time.

Wayne Connors December 13, 2021

Thank you for the heads up in laymans terms.

Gerald ward October 16, 2021

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