A lot of crops, like papaya and some citrus trees have been attacked ferociously by the mealybug in the Gambia this season (at least that's what my amateur conclusion is). Does anyone have any good advice about what to do, especially if you grow a lot and it's not just the odd tree in your backyard.
Katja: I have found that infestations are somewhat weather dependant here in Senegal, and that most plants are most susceptible when stressed (not enough sunlight, too little water, etc.). If you have the right plant in the right place and it's still getting attacked, try soapspray: it is very effective for mealy bugs. I use a spoonful of potassium based soap in litre of water. The soap dissolves the way coating they rely on for defense and protection from the elements. Usually one or two applications does the trick.
Most liquid soaps are potassium based. If you aren't sure, or are worried about the additives that might be in whatever liquid soap is available to you, spray a trial amount somewhere inconspicuous and check for plant damage the next day.
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