The citrus mealybug, Planococcus citri (Risso), is a major pest of greenhouse-grown horticultural crops. Systemic insecticides are often used by greenhouse producers in an attempt to prevent infestations or suppress citrus mealybug populations. However, minimal information is available on the efficacy of systemic insecticides against citrus mealybug populations when applied as a granule or water-soluble drench to the growing medium. We determined the efficacy of curative and preventative applications of six commercially available systemic insecticides against the citrus mealybug on coleus (Solenostemon scutellarioides [L.] Codd) plants. The systemic insecticides tested were imidacloprid, dinotefuran, thiamethoxam, azadirachtin, cyantraniliprole, and spirotetramat. The curative applications of dinotefuran, imidacloprid, and thiamethoxam resulted in citrus mealybug mortality that never exceeded 35%. Preventative applications of dinotefuran, imidacloprid, and thiamethoxam yielded only 50% citrus mealybug mortality. Azadirachtin, cyantraniliprole, dinotefuran, imidacloprid, spirotetramat, and thiamethoxam applied preventatively yielded mortality levels that never exceeded 22%. Even at 4× the label rate, none of the systemic insecticides provided >61% mortality of citrus mealybugs. We concluded that the systemic insecticides evaluated in these four experiments failed to provide sufficient control or suppression (≥80% mortality) of citrus mealybug populations on coleus plants under the parameters of our study.