Due to unusual weather patterns, various pests—especially mealybugs—are spreading rapidly and threatening the coffee yields of Dak Nong farmers.
Mealybugs Infesting Coffee Gardens
Mealybugs are among the most troublesome pests on coffee trees. Worryingly, they spread quickly and are difficult to control.
Nguyen Van Thanh’s family in Dak R’moan Commune, Gia Nghia City owns over 2 hectares of coffee. These days, Thanh has been using irrigation water to wash the coffee trees, removing moss and mealybugs.
In addition, he applies plant-protection chemicals to help strengthen the plants’ resistance and supplements the trees with multi-nutrient fertilizers. These measures help the coffee flowers bloom well and improve fruit set, thereby enhancing both yield and quality.
“Controlling mealybugs cannot be done with a single pesticide spray. You must follow their life cycle—especially the egg stage. About 5–7 days after the eggs are laid, young mealybugs hatch. That is when we need to spray to prevent them from re-infesting the crop,” Thanh explained.
Similarly, Pham Truong Tam in Bon Dăr, Quang Truc Commune, Tuy Duc District manages 5 hectares of coffee. In recent days, mealybugs have appeared densely on clusters of young coffee cherries.
According to Tam, these pests feed on the sap of the developing fruit. Heavy infestations slow cherry growth and, if not treated promptly, the clusters can dry out and ruin the upcoming harvest.
When mealybug infestations become severe, a layer of black sooty mold often covers the fruit clusters and leaves. This fungus reduces the leaves’ ability to photosynthesize, causing them to yellow and drop prematurely.
Control Measures
Provincial plant-protection officers warn that once mealybugs penetrate the flower pedicels and young fruit clusters, they are much harder to eradicate. Therefore, prevention is far more effective than cure.
To prevent mealybug outbreaks, farmers are advised to:
-
Regularly clean their coffee gardens and prune branches to keep the canopy open.
-
Combine pruning with irrigation and the application of phosphorus and potassium fertilizers to improve fruit set and strengthen the plants’ resistance to pests and erratic weather during the dry season.
Agricultural agencies across Dak Nong are working with local authorities to guide farmers in applying integrated pest management (IPM) practices to effectively prevent mealybugs.
If mealybug density becomes high and the risk of spread increases, it may be necessary to spray the entire affected area. Farmers can first use high-pressure water jets to dislodge the insects’ protective white wax before applying insecticides, which improves control efficiency.
When using plant-protection chemicals, farmers should strictly follow the “Four Rights” principle: the right pesticide, at the right dosage, at the right time, and using the right method to ensure high effectiveness.