Pests and Diseases Viewer

Pansy Powdery Mildew


Pansy Powdery Mildew

Usually appear in

All Year

Back to Pests and Diseases

Caused By:-     Various Fungi


Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
Pansy Powdery mildew is a fungal disease that is particularly prevalent in summer and autumn when the weather is warm and dry (or in very mild winters). It is caused by several fungal species from Oidium, Podosphaera, Sphaerotheca and others. Several of these fungal species are not host specific and can infect many vegetables (beans, cucumbers, courgettes, pumpkins, etc), fruit crop (such as apples, grapes and quinces), sweet peas, dahlias, roses, hydrangeas and African violets, to name a few. Infected plants are covered in a greyish-white mould, usually on upper leaf surfaces and young shoots. Powdery mildew will not directly kill pansies, but severe infections may reduce their vigour and speed up plant decline. The spores(conidia) are readily spread by wind and water splashes. The disease is usually observed on the upper sides of the leaves with a whitish fungal growth developing on the leaf surfaces in patches which eventually coalesce to cover the leaves, stems or buds. The infected areas dies or may become soggy.
The severity of the disease depends on several factors such as variety of the host plant, age and condition of the plant, and is especially severe in warm, dry climates. This is because the fungus does not need the presence of water on the leaf surface to infect it. However, if the relative humidity is high the problem will be worse, but it does not tend occur when leaf surfaces are wet. Therefore, Crowded plantings where air circulation is poor damp and in shaded areas makes the problem worse. Young growth usually is more susceptible than older plant tissues.
Picture by Department of Plant Pathology Archive, North Carolina State University,
See also these other Powdery Mildews Apple, Begonia, Hydrangea, Oak, Pea, Phlox, Powdery, Quince, Rose.
See also Downy Mildews Brassica, Downy, Hebe, Lettuce, Onion, Pansy, Pea.
See also other Mildews American Gooseberry, European Gooseberry, Gooseberry.


Powdery mildew does not like wet conditions, it is worst when the weather is dry. Therefore spraying the leaves with detergent may well prevent powdery mildew.
Baking soda is said to work well in controlling powdery mildew. Mix about half a teaspoon of baking soda to one litre of water. Too much baking soda will burn the leaves.
A to 9 mixture of skimmed milk is said to be effective in controlling powdery mildew.
Spray fortnightly with a sulphur spray, beginning as soon as the very first sign of powdery mildew appears, or even earlier if you know that the particular plant gets powdery mildew every year.

Back to top