Citrus mealybug on houseplants
On a houseplant the colony packs into leaf joints, leaf undersides and stem tips, and egg sacs turn up on pots and stakes as well as on the plant. Eggs hatch over an extended period and most sprays do not touch them, so one wipe or one spray leaves the next batch of crawlers behind — UC advises repeating alcohol spot treatments weekly until none are left. Crawlers walk to the next pot wherever leaves touch, and an old, heavily infested plant is often better discarded than treated again and again.
At a glance
- Damage
- White cottony clusters in leaf axils, sticky honeydew below
- Type
- Sap feeding
- Settings
- Indoors, Under glass, Garden
- Threshold
- Any colony — indoor plants lack the natural enemies that hold mealybugs down outdoors
- Release
- Cryptolaemus montrouzieri
- Rate
- 5 beetles per infested plant (Arbico), or 2–10 /m² per release across a bench (Koppert)
How to confirm it
Use a 10× lens. Citrus mealybug has a fringe of short, even wax filaments all round the body and, on many, a darker stripe down the back; two long tail threads instead point to longtailed mealybug. White cottony egg sacs in the colony fit citrus mealybug, which lays eggs — the longtailed species bears live young. A larger waxy insect that walks briskly may be a mealybug destroyer larva, not a pest.
Identification, lifecycle, degree days and every control option are on the full Citrus mealybug profile. Not sure it is this pest? Answer four questions about the damage.
Work it out
How many do I need?
Carries Cryptolaemus montrouzieri and houseplants through so nothing is re-entered. Open the calculator →