Crop rotations to prevent the successive plantings of several onion crops and interplanting with non-host crops can also be effective in deterring large populations. While the onion thrips can be readily killed by many insecticides, they are often difficult to control because of their small size and cryptic habits. Insecticidal control of this pest depends on the choice of an effective chemical and adequate spray coverage on parts of the plant where the thrips inhabit. For example, control of this pest on onions is exceedingly difficult because of the shape of onion leaves. Many larvae and thrips are found in the leaf axils which often do not receive insecticide deposits.
Thrips are shallow feeders that feed primarily on surface tissue.
Contact-residual insecticides are more effective. Systemic insecticides which transport through the plants vascular tissues are not as likely to be effective if they are not applied in a manner like other contact insecticides. Another important aspect of insecticidal control is spray intervals. Since eggs, prepupae, and pupae are not easily killed by insecticidal sprays, the time required for egg incubation and larval development must be considered. In order to control high population densities of this pest during warm, dry periods, repeated applications at 7-10 day intervals are required.