If your begonia develops mottled leaves, it could be infected with powdery mildew. Then you must act quickly. to save your plant.
Begonias are resistant to most pests and diseases. However, even with proper care, mildew can still occur. The fungal disease manifests itself as spots on the leaves. But beware: powdery mildew
is not the same as powdery mildew. Here you have to distinguish between the fake and the real. But no matter what it is: natural and chemical agents are suitable for combating it. Sufficient moisture is important as a preventive measure.
Downy mildew and powdery mildew on Begonia
Both downy mildew and powdery mildew are fungal diseases. Both damage the plant and lead to the death of the leaves. The infestation can spread to the shoots and leaves. This is how you recognize the infestation:
» downy mildew:
The downy mildew appears first on the underside of the leaves and forms a mosaic-like coating. The color can be brownish, bluish or greenish. Later, the coating also spreads to the upper side of the leaves.
» powdery mildew:
Powdery mildew is visible on the leaf edges in the early stages. It is a whitish-grey coating. The infestation will spread to the entire leaf if left unchecked.
Causes of powdery mildew
Begonias need adequate moisture to remain he althy and resilient. Usually the leaves of the begonia are fleshy to succulent. A leaf that is too dry therefore forms a good landing site for fungal spores. With room begonias, the humidity in the room also plays a role. A small infection is enough, which can break out even with the greatest caution.
Warning, now it gets tricky: powdery mildew can break out if the environment and the soil are too dry. Downy mildew, on the other hand, spreads when the climate is too humid. Too much moisture on the leaves in particular promotes infestation. It all comes down to the right balance!
How to prevent an infestation
The best prevention is thatyou observe your begonias on a regular basis. He althy begonias have intact leaves. For example, resilient begonia leaves feel fleshy and thick, yielding slightly to finger pressure. A possible infestation is quickly visible, but fortunately there are effective countermeasures.
Fighting powdery mildew: The best methods
» Milk-water mixture:
Kick off mildew with one really simple remedy: milk. It effectively expels the fungal parasites from the leaves! All you have to do is mix milk and water in a ratio of 1:9. Then spray the diseased plant with the solution twice a week. The latest research has shown that there are microorganisms in milk that fight the powdery mildew fungus. The contained sodium phosphate additionally strengthens the plant.
» Horsetail tea:
It is also helpful if you spray the begonias with horsetail tea (instructions for making the tea can be found here). In addition, you must also remove heavily infested parts of the plant and dispose of them in the household waste. Not the compost! Otherwise mildew could spread in the garden.
» Fungicides:
When natural methods don't help, a chemical antifungal is needed. Fungicides eradicate the fungi quickly and reliably. The sprays are not harmful to the plant. We recommend, for example, Compo Duaxo Universal mushroom-free (e.g. available here). But first try the tip with the milk. It has been found that milk is often even more effective than commercial fungicides. So before you resort to the chemical bludgeon, try the natural method first.
Summary:
- pay attention to a balanced moisture ratio
- Check leaves for infestation
- if powdery mildew appears, spray with a mixture of milk and water
- use an antifungal medication in an emergency