One of the most common diseases of parsley is powdery mildew – especially if the plants are grown outdoors. The fungal spores are already present in the soil and are promoted by too much wetness.
Powdery or downy mildew
When a whitish coating appears on the leaves, it is usually powdery mildew.
- Velvety coating
- White or grayish
- Top of leaf: powdery mildew
- Lower leaf surface: downy mildew
- Causes of powdery mildew
The fungal spores are already in the soil and spread when the plant is too moist.
Prevention against powdery mildew
Provide well-drained soil where waterlogging cannot form.
Do not water the plants too frequently, but only when the soil surface has dried, and do not wet the leaves.
Prick out the parsley to the ideal planting distance of ten centimeters, so that the leaves can dry well after rain or watering.
Tips & Tricks
Some gardeners swear by planting chives between parsley. This measure is said to effectively curb the appearance of powdery mildew.