If your bonsai tree is not looking very well, you might be wondering if it is still alive.
Six warning signs may determine whether your bonsai is dead, including:
- Brittle branches
- Loss of foliage
- Discoloration
- Odd leaf patterns
- Root abnormalities
- Dead wood in the trunk
Usually, a combination of these signs will indicate that your bonsai tree is either dead or dying. One alone may indicate some other issue is at play, but if there are multiple problems, your tree is probably in big trouble. We’re going to look at these signs and how to detect them in more detail.
Brittle Branches
One of the easiest ways to test the health of your bonsai tree is to put gentle pressure on some of the thinnest twigs. A healthy twig will be quite supple and should just bend under the pressure, rather than breaking (although it will break if you push too hard, of course).
An unhealthy or a dead twig will become brittle as the sap is drained out of it, and it will therefore break under pressure, usually very easily. You may hear a sharp snapping noise as it does so, although small twigs will snap very quietly.
If the twigs of your bonsai tree seem very brittle, you can also test one of the larger branches. This will give you an indication of how serious the problem is. If the bigger branches still have life in them, you may be able to save the tree – although not always.
Gently push on one of the bigger branches, and see if it breaks. It can take a long time for large branches to lose their suppleness even when they are dead, so one bending is not a sure sign that the tree is still alive, but it is an indication that it might be.
The brittleness test is nice and easy to do, but you do have to apply it gently. You don’t want to damage a healthy bonsai (or a sick but salvageable bonsai) by snapping off all its twigs and branches.
Loss Of Foliage
Like all sick and dying plants, a dying bonsai will quickly drop its leaves. This is because leaves take energy for the tree to sustain. They need nutrients and water, and if the tree is too sick to supply these things, or cannot access them, it will start to shed its leaves.
If you notice your bonsai tree shedding a large number of leaves, it is time to check it over for problems. Healthy trees do shed leaves, but usually only a few at a time (unless you have a deciduous bonsai, in which case it will shed leaves during the fall).
You should check if all the basic needs of your bonsai tree are being met. This could include:
- Light
- Water
- Nutrients
- Humidity
You should also check that your bonsai tree is not being attacked by pests. Infestations of pests can quickly devastate small plants, so make a regular habit of looking at your bonsai tree’s foliage and making sure that it does not have any unwelcome visitors on it.
Many insects are tricky to spot, and a particularly invisible one is scale insect. This is a small, brown, oval insect that manages to look a lot like a leaf blemish. If your bonsai tree has scale insects, you might find sticky specks of sap around.
Wipe scale insects away with vodka, and deal with other pests using soapy water. The sudden and unexplained loss of foliage must be explored promptly, because there may still be time to save your tree.
Discoloration
Discoloration on the leaves is also an early warning sign that something is wrong. It is not usually a sign that the tree is dead, however, most dead trees will have lost their foliage prior to death.
It is still worth including, as it is something you should keep an eye on. You need to know approximately what a healthy leaf should look like for your tree, and watch for any unusual changes.
Some color variation in the foliage is expected with any plant, but if your bonsai tree is inexplicably turning pale and dull, something is wrong. Some bonsai trees, such as juniper, will go from vibrant green to very pale green, and this is a sign that the tree is sick.
Leaf discoloration should be treated as a signal to look into what’s going on with your bonsai tree so that you can treat it quickly. It is important not to ignore changes in your bonsai. Because the trees are so small, they do not have great reserves of strength with which to deal with issues, so prompt reactions on your part are important.
Odd Leaf Patterns
Alongside discoloration of the leaves, patterns on the leaves can be a worrying sign too. Again, these are an early warning system, rather than a clear sign that the bonsai is dead, but if you noticed them on a tree that has since died, you will know what to look out for next time.
Some trees are vulnerable to fungal infections, and some of these can cause strange patterning on the tree’s foliage.
For example, powdery mildew will frost the leaves with white, and while it may not be deadly in many cases, you should still address it as quickly as possible to keep your bonsai tree healthy.
Black sooty mold will turn the leaves dark, stripping the vibrancy out of them, and again needs to be addressed before it kills the tree.
It is important to pay attention to foliage health because it does tell you how healthy the tree is.
Root Abnormalities
The roots of your tree are a part that you will rarely get a good look at, but if you think your tree might be dead, they are a very important thing to examine. Even if you don’t think your tree is dead, you should gently lift your bonsai out of its pot and inspect the health of the roots every so often.
Remember, a plant’s roots are the most important part, and you need to recognize whether they are healthy. If your plant is not looking very well, ease it out of its pot and examine the roots. They should be strong and supple.
You can compare your tree’s roots to pictures of other specimens online, as different kinds of bonsai trees will have different-looking roots. However, roots should always feel firm and reasonably dry. They should only be moist if you have just watered the plant.
Any wet or mushy roots should be cause for concern, especially if they have turned black. This is caused by over-watering, and it will quickly kill your plant. You will need to cut away the rotten roots with sterile scissors, and dry the rest out before you re-pot your bonsai tree into new, dry soil.
This will hopefully save it if the damage has not gone too far. Make sure you reduce its watering frequency to avoid similar issues in the future.
If you take a dead bonsai out of a pot and the roots are all black and mushy, the bonsai got over-watered and this has killed it. A bonsai tree that has lost all of its roots is dead, and cannot be saved.
Dead Wood In The Trunk
Another way to test the health of your bonsai tree is to scratch back some of the bark on the trunk and see how quickly you find fresh, green wood. This is similar to the brittle branches test, although perhaps a little more drastic.
You can do this with your fingernail for many bonsai trees. Simply scrape back the top layer of the bark, and see if the wood is fresh and green underneath. Green denotes life, so if your tree is still green, it is not dead.
If the layer beneath the bark is not green, continue scratching until you find green wood. If you reach the hardwood in the center and you have not found any greenery, the tree is sadly dead and there is nothing that you can do to save it.
It is best to do this scratch test on an inconspicuous part of your bonsai or make it a feature of it. It will likely heal over with time, but there may always be a scar on the trunk where you have broken it open.
Try to avoid this test unless you are really concerned that your bonsai has died because it will permanently change the tree’s trunk. You can do this test on branches as well as the main trunk if you like.
Conclusion
There are numerous signs that a bonsai tree has died, but the most significant will be the brittleness of the wood, and the health of the roots. If your bonsai has died, don’t be disheartened; learn from the experience and have another go!