Parsley is one of the most popular herbs in the kitchen. If you pay attention to their needs, you can cultivate them successfully in the garden. But where do the white spots on the leaves of parsley come from? What helps against that?
Table of Contents
Recognizing and combating causes
- powdery mildew
- Wrong mildew
- spider mites
- care mistakes
Powdery mildew is caused by fungi. More than a hundred different types of powdery mildew are known. In Germany, powdery mildew and downy mildew are the most common.
The dreaded disease occurs especially in dry, warm weather. The sac fungus forms large white deposits on the upper side of the leaves of various plant species. It penetrates the cell layer. It dries up and the affected parts of the plant die.
Powdery mildew becomes visible through a white, flour-like coating on parsley leaves. Gradually the surface becomes darker. It turns brownish to greyish and can be easily wiped off.
Mildew pathogens are spread by the wind. They get on the leaves of endangered plants. When they reach the parsley leaves, they penetrate the cell layer and form a mycelium.
Downy mildew becomes visible on the underside of leaves as gray deposits. When infested, white spots appear on the upper side of the parsley leaves.
Downy mildew needs moisture to develop. Water accumulations that stand on the leaves after long rains create the perfect basis for the spread of the ascomycete fungus. The spores swim in the water droplets, penetrate the cell layer and damage it.
In contrast to powdery mildew, the fungal spores of downy mildew overwinter in fallen fruit and leaves.
combat powdery mildew
Various fungicides to combat powdery mildew are available from specialist garden retailers. Do not use these chemicals on crops. We show how you can successfully combat the sac fungus with natural measures.
1. Remove affected plant parts
If you notice white spots on parsley or other plants in the garden, cut off the affected parts of the plant. Only use clean knives and scissors. Disinfect them carefully after use.
2. Discard the plant if it is heavily infested
If your parsley is already clearly infected with powdery mildew, dig up the plants and destroy them completely. Dispose of affected plant parts or whole plants in household waste or in the organic waste bin. They don’t belong in the compost! The fungi can survive in the compost for a long time and infect other ornamental and crop plants.
3. Spray with baking soda
Baking soda is available in most households, after all it can be used universally. It’s even a good help in fighting powdery mildew.
- 1. Put one packet of baking soda in two liters of water.
- 2. Add 20 milliliters of oil.
- 3. Pour the mixture into a spray bottle and spray the parsley leaves with it.
4. Spray with onion broth
- 1. Slice an onion.
- 2. Pour a liter of boiling water over the onion slices.
- 3. Let the mixture steep and cool.
- 4. Pass the onion broth through a sieve and fill it into a spray bottle.
- 5. Spray the parsley thoroughly with it several times.
Although powdery mildew is the most common cause of white spots on parsley leaves, spider mites can also cause white spots. Spider mites prefer to sit on the underside of parsley leaves and are not choosy about their host plants. They are among the most common garden pests.
Symptoms of a spider mite infestation
- white or silvery spots on the upper surface of the leaves
- visible mites on the undersides of the leaves
- fine threads
- Discoloration and drying up of the leaves
Fight spider mites
1. Remove affected plant parts
Cut off the affected parts of the plant. Use a clean, sharp knife. Disinfect the cutting tool thoroughly after use. Dispose of the parts of the plant in household waste or in the organic waste bin.
2. Rinse off spider mites
Spider mites don’t like moisture. Periodically spray the parsley thoroughly with water. You can rinse off parsley in the pot in the shower.
Another cause of white spots on parsley leaves can be care errors. These include, above all, a wrong location , unsuitable because exhausted substrate or an incorrect water supply.
If the parsley is too sunny, for example, it quickly gets sunburned and the leaves show whitish-yellow spots. The same applies to the herb when watering: less is more. Only water the parsley when the substrate is dry. If other umbellifers have been grown at the same location in the recent past, the nutrients are no longer sufficient and the plant “thanks” you with stunted growth and the formation of spots.
- Place the plant in a bright spot out of direct sunlight.
- Loosen the soil around the plants.
- Pull weeds regularly.
- Remove diseased, dry plant parts.
- Cut the parsley continuously.
- Obtain suitable fertilizer from specialist retailers.
frequently asked Questions
The best measure to prevent plant diseases is to design the garden in a way that is close to nature. In gardens where beneficial insects thrive, pests and diseases have little chance of spreading. Ladybugs are an excellent help in this. They eat powdery mildew with pleasure.
Parsley and sage often suffer from powdery mildew or downy mildew. Plant the popular herbs between chives, chervil and basil. In the herb bed, the plants build up effective protection against powdery mildew and other diseases.
You can buy predatory mites in specialist shops to help against spider mites. With parsley, which can be easily re-grown, this effort is too high. If the infestation is severe, we recommend digging up the herbs, destroying them and buying new plants.