Content
Too much moisture can lead to mildew
Mildew on the petunias: diagnosis and countermeasures
For optimal growth, petunias on the balcony not only need lots of heat and light, but also enough water and nutrients. However, it can sometimes come despite optimal conditions to a larger infestation with diseases such as mildew.
The downy mildew
The downy mildew can be recognized by its light or brown spots on the leaf tops and on the floury coating on the leaf undersides. A strong infestation can lead to a dying of the plants. Small lesions should be cut out immediately to reduce spread. In addition, a location protected from rain should be selected for the petunias. When watering the plants you should never water the plants as a whole, but always pour close to the roots.
The powdery mildew
The powdery mildew is like the downy mildew also a fungal disease, but is primarily stuck to the leaf tops. The spread of spores is favored by the change between moisture and dry phases on the leaves and stems. If the affected areas are not removed, the powdery mildew can not only kill the petunia, but also skip the following plant species:
Tips
Since the downy mildew can also multiply on the dead plant parts on the compost heap, cut plant parts should be disposed of in the doubt about the household waste.