The foliar application of the parasitic nematode Steinernema feltia (Filipjev) (Rhabditida: Steinernematidae) is being reported by growers to provide successful control against Western flower thrips (Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)) in ornamentals. Currently, the susceptibility of different developmental stages of WFT to S. feltiae is being tested in the laboratory and the efficacy of application on chrysanthemum flowers or foliage is being compared. Finally, the survival and infectivity of nematodes will be tested at different intervals after application on chrysanthemum under greenhouse conditions. Understanding factors like differential mortality among thrips instars, the influence of plant stage and the survival of nematodes after application will improve the efficacy and reduce the cost of this control method.