Recognize and treat diseases

Powdery mildew in petunias

The real mildew is a fungal disease that can spread quickly in dense populations of petunias without treatment. Powdery mildew is more likely to occur when it comes to petunias that are exposed to wet, rainy weather without a protective roof. Permanently wet weather ensures permanently moist plants, which is also due to their growth are not dried well by the wind and sun, powdery mildew usually does not last long wait. He's on that white covering recognizable, which can cover all parts of the petunia like a flour-like layer. Possible prevention and treatment options are:

• the regular removal of dead flowers and parts of plants
• the installation on a rather dry one Location
• spraying with a water-milk mixture (9 parts water, 1 part milk)
• cutting out infected parts of the plant

In contrast to downy mildew, powdery mildew only thrives on living plants, so distant petunias can be composted safely.

The neck rot

The so-called root neck rot is a disease that is transmitted with the plant substrate used. The upper root area and the stem base turn black or brown before the entire plants wither and die. In such a case, the petunias can no longer be saved. However, you should replace the potting soil and dispose of the old substrate if possible (not on the compost). So take precautions that the newly bought or out Seed grownYoung plants not be re-infested with the root neck rot.

Chlorosis: a symptom of deficiency

Chlorosis is the name given to leaf yellowing, which in petunias usually occurs on the young leaves. Strictly speaking, this is not a disease, but a deficiency symptom due to insufficient nutrients in the plant substrate. This often occurs when petunias are in the same Balcony box for several years without any significant fertilization overwintered will. Since it is usually a chlorosis due to iron deficiency, foliar fertilization with a special iron fertilizer often helps.