Protective Row Covers for Management of Flea Beetles in Organic Eggplant Production in the Southeastern US

Organic eggplant production in the United States is challenged by flea beetles, which stunt eggplant growth and reduce yield. Across four experiments between 2019 and 2024, we compared the effects of various pest management strategies on flea beetle abundance, damage, and marketable yield in eggplant production, focusing on row covers and organic insecticides in later years of the study. Treatments included fine-mesh row covers, organic insecticides, and untreated controls (all years); reflective plastic mulch (2019); various essential oils (2019–2020); conventional insecticide control (2019–2020); and spunbonded row covers (2019–2021). Low flea beetle pressure was observed in 2019 and 2020; consequently, experiments were moved to fields under organic management with more frequent cultivation of solanaceous crops in 2021 and 2024. Samples taken near row cover removal at flowering revealed significantly more flea beetles in the control than fine-mesh row cover treatments in 2019, 2020, and 2021. However, there were never significant differences in flea beetle abundance in samples collected at transplanting or at harvesting. Flea beetle feeding damage at flowering was significantly lower in all row cover treatments than the untreated control in 2019, 2021, and 2024 and the organic insecticide treatment in 2019 and 2021; data was not collected in 2020. There was no difference between treatments in marketable yield in 2019 and 2020; however, the marketable yields of fine-mesh row cover treatments maintained over the entire growing season were 82% and 471% higher than the organic insecticide treatments in 2021 and 2024, respectively. These results indicate that fine-mesh row covers may be a viable pest management strategy in organic eggplant production.