If the apples are already rotting on the trees, it is of course a big disappointment for every hobby gardener, because these fruits are no longer suitable for harvesting.
Monilia fruit rot makes apples moldy
In the most common cases, the cause is a tree fungus that spoils the fruit. It is the so-called Monilia fruit rot that is transmitted by the tree fungus called Monilia fructigena. The fungus enters the fruit through tiny injuries. A cracked scab or damage to the bark by wasps is enough for the fungus to be able to wreak havoc on the fruit. Wide brown rotten spots are delimited by a whitish ring-shaped fungal spore bed and are the typical signs of fungal infestation.
Fighting Monilia Fruit Rot
Infection with Monilia fruit rot usually starts from plants and parts of plants that are already infected. Therefore, remove all sources of infection regularly and meticulously.
Step 1:
As a preventive measure, take off the stunted fruits, known as fruit mummies, in the winter. Also collect the fallen apples. These fruits are often affected by the fungus and the new shoots then become infected in the flower (transmission by spores).
Step 2:
Leaves of the infested tree that are on the ground must also be removed thoroughly. In this case, the leaves should end up in the bin, not in the compost, so that the fungus cannot continue to multiply in the garden.
Step 3:
Cut diseased shoots back into the wood well below the infected area.
Preventing Monilia Fruit Rot
The risk of infection with Monilia fruit rot can already be contained when apple trees are planted. Opt for apple varieties that experience has shown are not very susceptible to monilia fruit rot and plant them in a sunny and airy location. This improves ventilation and enables rapid drying after precipitation. It is generally more difficult for fungi to infect the trees. It is precisely for this reason that a regular one is recommendedClearing of the treetops.
Tip: Make sure, however, that you do not carry out such pruning measures while the trees are bearing fruit. Otherwise the apples could get sunburnt and start to rot.
Make sure your apple trees are fertilized in a balanced way. You can also use special plant strengtheners to increase the resistance of your trees.
Since the fungus can also penetrate the fruit through damaged areas, you should avoid injuries and wounds as much as possible. Such can be caused, for example, by apple tree pests, such as the codling moth, or birds. To keep them away from your fruit, you can, for example, attach bird netting to your trees.