Bonsai leaves turning yellow can be a frustrating situation. The good news is that it’s often easily remedied, but it’s a good idea to know why your bonsai leaves are turning yellow before you start fixing the problem.
Overwatering
One of the most common causes of bonsai leaves turning yellow is over watering. This happens when you’re trying to make your plant grow faster, but the root system isn’t able to accommodate the extra water. It can eventually lead to rot, which will kill your plant!
Over fertilization
The second most common reason for bonsai leaves turning yellow is over fertilization. This happens when a plant receives too much of a particular nutrient and not enough of another.
Pruning
Over pruning can also be a cause of bonsai leaves turning yellow. It’s best to only trim your tree when it is healthy and has fully regained its green leaves.
Wiring
Structural wiring can be a great way to shape your bonsai, but it needs to be done only when it makes sense for the particular branch. If you leave wires on for too long, they can actually bite into the bark and damage the sap flow.
Leaf fall
Autumn is a normal time for bonsai leaves to turn yellow and drop off. It’s usually a sign that the bonsai is preparing for winter dormancy.
Pests
When your bonsai is attacked by pests, you’ll see brown spots on the leaves. Different species of pests have their own specific problems, so it’s important to know which ones your bonsai is dealing with so you can tackle them properly.