Mealybugs
How to get rid of the pests
Mealybugs are also known as mealybugs or root lice. Their name says it all: they look as if they are surrounded by white cotton wool. They form a subfamily of the scale insects, which includes around 1000 different species. There are two main species in Europe: The citrus mealybug (Planococcus citri) and the long-tailed mealybug (Pseudococcus longispinus). Like aphids, they also suck on leaves and stems, but also on roots. Mealybugs also secrete honeydew, which can cause the black sooty mould fungus to form on the plant parts. The leaves of infested plants turn yellow and fall off after heavy infestation. Infestation on potted plants can also be recognised when repotting, when white smear marks appear on the inside walls of the pot. Plants favoured by mealybugs are
- grasses (bamboo)
- composite plants
- legumes (beans, peas, ...)
- houseplants (orchids, rubber trees, alocasia, yucca palms, ...)
- citrus trees
- olive trees
- oleander
- hydrangeas
Prevention
- Appropriate location: sufficient light and good ventilation, avoid dry, heated air for indoor plants
- Balanced fertilisation: not too much nitrogen, rather potassium-rich, in the garden with nettle or comfrey manure
- Establish natural enemies: Ladybirds, parasitic wasps, lacewings, ... through natural, wild garden elements such as deadwood or piles of stones, insect hotels, flowering meadows, hedges.
Treatment
- Isolate affected plants if possible, ideally in a light and cool place
- Mix alcohol and curd soap: 15 ml alcohol and 15 ml curd soap to 1 litre of water, spray the plant every 2-3 days
- For root infestations on potted plants, repot, remove the substrate from the roots, rinse and use a new container: Repot, remove the substrate from the roots and rinse, use a new pot and disinfect the old one with alcohol
- Attract beneficial insects such as lacewings or parasitic wasps
- Neem oil
Bild von Frank Vincentz CC BY-SA 3.0
