Why are the leaves of my geraniums discoloured?
The plants are only 1-2 years old, are all potted plants. Some leaves have a mottled appearance as per photo. On occasion, back of some leaves look like they have been invaded but can't see any pest
Geraniums are very prone to rust which is seen on the underside of the leaves as brown pustules. Caterpillars such as green loopers also enjoy eating the leaves. I suggest you try a product like Yates Rose Shield which contains both a systemic fungicide and insectide. Water under the leaves and this will also help reduce the incidence of disease.
Answered: 8 Oct, 2011