If an apple tree shows signs of disease or other problems, it is often not so easy to determine the cause. If the tree suddenly gets yellow leaves in spring or summer, there can be various reasons.
Why does my apple tree have yellow leaves?
Yellow leaves on the apple tree can be caused by fungal infestation, inadequate tree pruning, wrong planting time, lack of water supply, stony soil, voles or pests. To resolve the issue, you should identify the cause and take appropriate countermeasures.
Fungal infestation, mildew and scab
The most feared diseases in apple trees include powdery mildew and so-called apple scab. Both diseases are not actually a yellowing of the entire leaves, but rather the following symptoms:
- the leaves show rusty brown spots
- Fruits have black spots with cracked center
- the spots spread from the center of the leaf to the outside
However, yellow leaves can also be caused by a fungal disease. This in turn is not only due to a lack of resistance of the respective apple variety, but often also to inadequate pruning.
The yellowing shortly after transplanting
If the leaves turn yellow shortly after planting or transplanting a young tree, this may also be the reason for the damage. For example, if the apple tree was planted in the middle of summer or on a hot spring day, the roots of the apple tree may have dried out too much. The reason can also be a lack of water supply or soil that is too stony with little loose root substrate. For these reasons, when planting an apple tree, not only should a suitably prepared planting hole with sufficient size and humus-rich substrate be available, but the time should also ideally be chosen in the fall after the leaves have fallen.
Rodents and other pests
The yellow color of the leaves usually indicates a disturbance in the apple tree's sap balance. This can also be due to damage to the roots by voles and other pests.
Tips & Tricks
Voles cannot only be driven away with chemical agents, mechanical traps and the electronic vole deterrent (€22.00 on Amazon). Transplanting the tree trunk with currant bushes provides natural protection, as voles do not like their smell.
