Insecticidal soaps and horticultural oils work great in controlling this pest. The tricky part is mealybugs tend to hide very well where leaves attach to the stem, so make sure you get coverage there. Horticultural soaps and oils don't have systemic properties, which means when spraying, the product must come in contact with the pest. So know where your pest is on the plant.
A word of warning: You can burn leaves with horticultural soaps and oils. These products need to be applied when the air temperature is cool. Make sure your plants were watered well the day before you apply your control - never spray wilted plants. Following labeled rates also reduces the risk of leaf damage. More is not better. Also, make sure beneficial insects are not present when you spray. (Insecticides can kill the good guys, too.)
*this info was found by googleing the Mealy bug !