Citrus mealybugs are a little sap-sucking insect, grey with a dusty white waxy covering. They tend to affect glasshouse plants or houseplants as they require warm temperatures to survive. They tend to live together in dense groups, in protected parts of plants. As they suck large amounts of sap from plants, to gain sufficient nutrition, they produce a sticky, sugary substance, called honeydew. This honeydew falls on to the leaves below infestation, and a grey mould called sooty mould may develop. This mould may reduce the plants' ability to photosynthesise. Activity is reliant on temperature but can be found on plants indoors or glasshouses most of the year. Summertime infestations are most common. There are many generations in a year if conditions are continuously warm.
Mealybug feeding encourages the growth of harmful mould.
Severe infestations can stunt the growth of plants.
Adults: Adult Citrus Mealybugs are about 3mm to 4mm in length. They are grey with a dusty white wax covering to the body. Nymphs: The nymph stage of the Citrus Mealybug development looks like a mini version of the adult. Eggs: Tiny eggs are laid in clusters and are covered with the same white dusty wax as the adult.
Small patches of the dusty white wax at leaf joints, the underside of leaves or on central vein (or other tucked-away areas). Sticky substance on the top side of the lower plant leaves, known as Honeydew. Black or grey sooty mould on leaves. Stunted growth.
Squashing with fingers and hand removal. Check all new plants coming into the growing area to reduce the opportunity of introducing pest to your other plants. Biological control Crytolaemus montrouzieri (a specific ladybird) can be purchased online. Need to be used in an environment such as a sealed glasshouse or they may leave if windows or doors are open.
Few chemical controls are suitable because of the dusty wax covering the Citrus Mealybugs, most chemicals are repelled. Please check with your local Garden Centre for up to date chemical availability.
Many ornamental House plants and Citrus plants.