Mealybugs are tiny slow-moving insects, covered with a pale 'mealy' powder like coating, that suck sap from plants and spread disease.
Identify the problem
Mealybugs (or mealy bugs) are tiny insects found on plant stems and leaves (see also root mealybugs). In spring, newly hatched mealybugs known as 'crawlers' move onto young shoots where they settle on the underside of leaves. These areas can be difficult to spray, but effective coverage is the key to mealybug control.
Mealybugs are covered with a pale 'mealy' thread-like or powder-like protective coating. The bugs feed by sucking on the plant sap. Mealybugs excrete a sticky substance called honeydew which ants and wasps like to feed on. Ants may farm mealy bugs by protecting them from attack so that they can feed on the honeydew.
The honeydew also provides a perfect medium for sooty mould growth. Often leaves of infested plants have sticky white patches of bugs and/or black sooty mould.
Mild temperatures and high humidity are perfect conditions for mealybugs to breed but prolonged hot weather reduces numbers. Damaging infestations can occur on citrus trees, daphne, and other ornamental plants. Orchids and ferns, especially in greenhouse, can also become infested. Mealybugs will attack bulbs in storage and the roots of some plants.
To get rid of mealy bugs follow these steps:
- Mealy bugs are difficult to control because they hide where leaves join stems or in flowers, and their mealy coat helps to repel insecticides.
- On ornamental plants apply PLANThealth Spectrum.
- Kiwicare Organic Super Spraying Oil effectively kills mealy bugs by suffocation, however do not spray in the middle of the day or in hot weather as this can cause burning of the plant.
- Check for and control ant populations that might be farming the mealy bugs, protecting them from natural predators. More information on controlling ants in the garden.
- Remove mummified fruits. In warmer regions, mealy bugs may survive over winter amongst long grass and weeds, removing these helps reduce the mealybug population.
Control Ants and the Sap Sucking Insects they 'Farm' in Trees, Shrubs and Ornamentals
- Apply LawnPro Protect on the the soil around the roots of affected plants. This kills and prevents ants moving up the plants.
Did You Know
- Mealy bugs (see also root mealybugs) are members of the family - Pseudococcidae.