Bonsai trees, much like people, tend to show physical signs when something is going wrong. A bonsai tree having brown leaves signifies that the tree is having an issue, which could be anything from over-watering, under-watering, disease or even heavy pruning. A tree with brown leaves isn’t always a dead tree, so in this article we are going to help you find the root cause of the issue and show you exactly how to solve it fast.
Why Your Bonsai Tree Has Brown Leaves
Before we can actually save your bonsai tree, we need to try to isolate the root cause of why your tree has brown leaves. Trees are fairly resilient, they only really show any sort of signs of an issue once there is a really big issue. For a bonsai to be showing brown leaves, there must be a pretty serious problem. To find this problem, work down this list below, referencing the symptoms of each possible reason to narrow down which is likely to be the cause. With any luck, it’s not too late and your bonsai can still be brought back to vigor.
Possible Reason 1 – Over-watering Or Under-watering
Without a doubt, the most common reason why a bonsai will be showing brown and dry leaves will be due to a lack of water. A lot of people will either forget to water a bonsai tree for a few weeks, or have a watering schedule that really doesn’t line up with what the tree actually needs. Looking at bonsai trees as a whole, the majority are going to need a thorough water every 2-3 days, with that increasing to once per day in the summer months. If you are watering your tree just a few times a month, that is definitely a potential reason as to why the leaves are dry and brown.
Also using a watering schedule can lead to the same fate. Trees, just like humans, aren’t forever going to need the same amount of water at the same time, year round. With different temperatures, humidity and growth cycles it’s nearly impossible to create a schedule that automates the watering process. To achieve a healthy bonsai tree over the long term you need to have a hands on approach to checking and watering your tree. For a full guide on watering a bonsai, check out this article I put together!
How To Water A Bonsai Correctly
I have written a full watering guide
here, so check that out if you are unsure on whether or not you are watering correctly. A quick run down of this process though…
Push your finger about 1 inch into the soil to feel for moisture. The perfect time to water would be when the soil is damp, not soaking. If the soil is bone dry, you have left it too long since the last watering.
Pour water all over the top soil from a low height, evenly. Keep going until water is streaming out of the drainage holes on the underneath of the pot.
Leave the water to drain out for 2 minutes.
Repeat the watering process once more.
That is a basic guide in watering your bonsai tree.
Looking At The Bonsai Pot
If you have owned a bonsai tree for 2+ years and never re-potted it or changed the soil, there’s a good possibility that this could be leading to your tree having brown leaves. In most bonsai soil mixes, if they contain organic material, they will start to break down after a few years which leads to the soil not being able to absorb a lot of water or nutrients. This means that even if you think are you giving your bonsai tree a lot of water, it could potentially be flowing straight out of your drainage holes.
Again if you haven’t re potted for over 2 years, there is the potential that the root system is so squashed and compact that it is struggling to take up any water. Although the point of growing a tree in a pot is to stunt the growth of the root mass, if this gets too compact no matter how much you water the soil, it really isn’t going to make any difference to the health of the tree.
Last of all, does your bonsai pot have 2 or 3 drainage holes? If not, there is most likely going to be a lot of water retained in the actual pot itself. Although to some this may seem like a good idea as the tree won’t be dehydrated, it will actually cause the roots to weaken and start rotting. Once root rot has set in, it’s extremely hard to nurse to tree back to health and takes a lot of harsh pruning.
Symptoms Of Over-watering and Under-watering
-Roots pushing out of the pot.
-Brown, dry, crispy leaves.
-A lack of growth in the tree.
-Branches feeling very fragile or brittle.
-The leaves are yellow or brown and drooping.
-The trunk of the bonsai is flimsy or soft.
-The roots are rotting.
Possible Reason 2 – Environment
The environment a bonsai tree is living in can play a huge factor in the health of the tree. The general view for most beginners, myself included, is that bonsai trees are just indoor trees as they are tiny and grow in pots, like house plants. This couldn’t be much further from the truth, bonsai trees are not like house plants at all! Different bonsai species will need very different growing conditions to thrive, most of which are not indoors.
It’s important to understand what species you are growing as this is a huge factor in where the tree should be growing. It’s worth searching the forums to see what your actual species needs to thrive but one thing all bonsai trees do have in common is the amount of light they need. All trees thrive off a high level of sunlight and a lack of that can and normally result in brown leaves, which may be the reason for your tree browning. If you feel like this could be the issue for your bonsai and the cause of the brown leaves, it might be worth having a read of this article I put together detailing where to put your bonsai tree
for optimum growth!
Factors To Be Considered
-The climate in your country
-The time of year
-The species type (Tropical, Subtropical, Hardy etc).
My Chinese Elm Story
To hammer home the impact of the environment, I’ll mention my Chinese Elm bonsai from many years ago now. The Chinese Elm should be grown outside pretty much all year round, only really coming indoors for cold snaps or other extreme conditions. I had absolutely no idea how to look after my bonsai at the time, so my tree was living indoors, the for whole year, near my radiator. Even though I was caring for it, watering it every 2 days, pruning it (over pruning it, looking back), the leaves were browning and something was definitely wrong. It wasn’t until I researched more I realised that the tree was growing in the complete wrong conditions. The lack of light and massive levels of humidity caused by the radiators were slowly killing off the tree, even though I thought I was looking after it. Conditions are extremely important!
Possible Reason 3 – Heavy Pruning
Bonsai trees don’t always respond too well to pruning, which is no surprise! Different species can react differently of course and the severity of the pruning can be a huge factor in how well it is received by the tree. Typically when removing branches or some of the larger shoots of your tree, parts of the foliage can start dying and turning brown in color. As annoying as this is, pruning is a necessary part of bonsai so it cannot always be helped. There are a few tips I can share to limit the stress of the tree when pruning, so they could be implemented into your process.
Firstly, not pruning everything all in one go. There shouldn’t really be a need to prune off a huge amount of branches and foliage in one go, unless you’re actually defoliating the tree
. Prune a section of the foliage, then give the tree ample time to recover before pruning any more off, this allows for less stress. Secondly instead of using a pair of pruning scissors, some bonsai experts actually hand pinch the foliage off, as to be more gentle to the tree. Although this can be a lot more time consuming it is definitely a lot less stressful for the tree so bare that in mind next time you are pruning. For a full pruning guide, have a read of this article I recently published with step by step tips to successfully pruning a bonsai.
Reviving Your Bonsai Tree (Step By Step Guide)
Step 1 – Finding The Issue
The first step in solving any problem is to know what the problem actually is. After referencing all of the signs and symptoms listed above, you should have a rough idea of what has gone wrong in leading your bonsai to having brown leaves. I would assume for the majority of readers it’s going to be a lack of watering but still it’s worth exploring every avenue to ensure that you haven’t missed something like a disease or the wrong living conditions. No matter how we try to save the tree, if the root cause of the problem is still present, it’s only a matter of time until the tree is in the exact same situation.
Step 2 – Pruning Where Possible
Take a look at the foliage and see if there are any spots that look dead or potentially infected. There is absolutely no benefit to keeping these on your bonsai as they are only going to hinder our progress in terms of bringing the tree back to health. Don’t look for large branches to remove as the tree is in a weak state at the moment, any huge pruning is going to be too aggressive for the tree. Any small parts of dead foliage, take a clean pair of pruning scissors and cut them away.
Step 3 – Checking The Root System
The heart of the tree is the roots, so you will need to check out the situation under the soil to see if there are any dead roots, rotted roots or tight root balls. To do this slowly start wiggling the tree out of its pot, holding it by the base of the trunk, slowly pulling it out of the bonsai pot. Once out of the pot, check the roots situation. If there are any dead roots or visibly rotting, immediately cut those away with a clean pair of pruning scissors. The next step would be to start untangling a lot of the root mass – once done, you should be able to see the extent of the root issue. Cut away whatever is dead or rotting, which could be up to about a third of the whole root mass depending on how long the tree has been struggling for.
Once you’re finished the the root pruning, you will want to repot the bonsai in a new soil mix. You can either pick up a standard soil mix, like this potting mix on Amazon
, or create your own bonsai soil mix.
Whether you are using a premade soil mix or creating your own, get it ready to be put into the bonsai pot. Cover the drainage holes with wire mesh sheets, the pour in enough soil mix to cover about 1/4 of the bonsai pot. Then you’ll want to put the bonsai tree into the soil, filling up the rest of the soil around it. Don’t pack the soil too tight as you still need aeration for the roots to get oxygen.
Step 4 – Water Bath
Now your bonsai has been repotted, it’s time to water it. Fill up a container, bigger than the bonsai pot, with water. Place the pot into the water, allowing it to come about 3cm above the top of the soil. Leave the tree sat in the water bath for about 2 minutes, before taking it out and allowing all of the water to drain out through the holes. This is the perfect opportunity to check that the soil is a great mix too as you should be seeing a decent level of water retention, as well as a good amount of drainage.
Step 5 – Environmental Healing
You have now done everything possible to save the bonsai tree – it’s just about giving it the time and conditions to fully recover and flourish now. For a full guide on where to place your bonsai tree, check this. Most importantly you need to place it somewhere with a lot of air, light and out of direct sunlight. The next few weeks are going to be extremely important for the tree since pruning away any dead roots and repotting, so it’s very important to ensure that the tree is getting the right conditions for healing. Make sure to keep the tree well watered and partially shaded over the coming weeks.
Dry and brown leaves are usually caused by the tree having some sort of serious issue, whether that be disease, lack of water, over-watering or more… What’s important is to narrow down the possible causes of this, so you can start nurturing the tree back to vigor. By looking at the symptoms above and following the step by step guide you should be able to nurse the tree back from health and the next growing season should be amazing for your bonsai. Please feel free to leave a comment with any questions or tips you may have that could be useful for others in this situation!