For many people, apple trees are simply part of the garden. They have beautiful flowers, provide the perfect shade and bear delicious fruit in summer and autumn. It's all the more annoying when the leaves of your favorite tree suddenly wither, curl or turn brown. In the article we explain which apple tree diseases often affect the fruit tree and what you can do to save the harvest.
Common apple tree diseases on the leaves
Diseases are caused by viruses, fungi and bacteria. They cause leaf loss, discoloration and deformation, first on the leaves, then on the fruits and then - on the bark of the tree. Some diseases are very dangerous and must be treated as quickly as possible so that the tree can recover. We give you an overview.
Apple tree leaves have brown spots: recognize and combat apple scab
Apple scab is a fungal disease that primarily affects fruit trees. The disease first becomes noticeable on the new leaves. Initially, many small brown spots appear, which then become larger and larger. Then the fruits are also affected. Brown spots, cracks and corking appear on the fruit bowl.
An important prerequisite for the pathogen to spread is the weather. The trees are usually attacked during the flowering period in spring. Frequent rains do not allow the leaves to dry and make them more susceptible to fungal attack. The young leaves are particularly easily infected.
Control is particularly possible with potted plants - because they have a compact growth, the trees can be treated more quickly. For this purpose, the diseased plant parts are first removed and disposed of with household waste. Then treatment with fungicide is carried out.
For large apple treesTreatment with fungicide is often the only option - although this is not always effective. As a preventive measure, large trees are thinned out in spring so that all the leaves can get sunlight and the trees are limed.
The fruit tree has yellow leaves that curl: curl disease
Curling disease is also caused by a fungal pathogen. The leaves curl up, turn reddish brown and dry out. If the disease is not recognized and treated in time, the affected leaves die in mid to late June. Significantly fewer fruits are born, they remain small and ripen much more slowly than usual. Even if the disease is successfully combated, you have to expect a low harvest next year.
The treatment is carried out using approved pesticides for private use. But this should happen before the buds form in early spring. Anyone who missed the deadline can now remove the affected plant parts and then have to wait until next year. Typically, most apple trees are able to keep the fungus at bay for a year and can survive the infestation. But if they are not treated in the next year, they will be so weakened that they could die.
Apple tree diseases: recognizing fire blight
Fire blight is caused by bacteria. They primarily attack fruit trees and are very dangerous. If the trees are not treated in time, they can die. The bacteria first attack the young leaves and flowers, which first turn dark brown and then black. The clinical picture is very typical - black shoots, leaves and flowers that dry up.
The disease is so dangerous because it spreads very quickly and there is hardly any treatment. Various variants of antibiotics are repeatedly tried in landscaping, but their use is not permitted for private purposes. In many regions there is therefore an obligation to report - you should inform the plant protection office at the first signs. The diseased plant parts are then immediately removed and the tools disinfected.
Apple tree diseases: powdery mildew
Powdery mildew is a fungal disease that affects not only trees, but also various vegetables and even ornamental plants. In apple trees, the disease occurs in two stages - the first in spring and the second in summer. If the plant is not treated in time, the tree will not be able to form healthy flower buds and will not bear fruit.
Fortunately, mildew can be controlled fairly quickly. There are both fungicides and home remedies that give good results. A milk and water solution can quickly solve the problem.
Apple tree diseases on the trunk: fruit tree cancer
Most apple tree diseases first become noticeable on the leaves. An exception is fruit tree cancer. It is caused by a fungus that attacks the trunk and branches. In spring and summer you notice discoloration on the bark. These places sink. The difference between the healthy and diseased bark is visible. The affected branches die and cracks appear in the bark on the trunk.
There is no treatment for fruit tree canker. The only thing you can do is cut off the affected parts of the plant.
