Cotton yields have suffered losses from cotton boll rot during the last 10 to 15 years in areas of South Texas. Piercing-sucking insects feeding on cotton bolls, particularly stink bugs, have been implicated in introducing the bacterial disease. Along the Gulf Coast of South Texas, boll-feeding plant bugs occur, and may be associated with the disease. A replicated field survey was conducted in 2010 and 2011 to assess relative abundance of these boll-feeding species and subsequent boll injury caused by cotton boll rot. This survey was paired with a field cage experiment that isolated feeding by the verde plant bug, Creontiades signatus Distant (Hemiptera: Miridae). This species represented about 99% of insects collected, during peak bloom (about wk 3 to 4 of flowering) in cotton fields near the coast. It was not detected in fields located further inland. Cotton boll rot was found on up to 25% of open bolls and was concentrated in coastal fields. The proportion of green bolls with cotton boll rot estimated two weeks after insect sampling was not linearly related to verde plant bugs per plant, but the subsequent proportion of open bolls with cotton boll rot near harvest was linearly related to verde plant bugs per plant (adjusted r2 = 0.53, P = 0.007). In field cages, verde plant bug-infested plants had significantly higher incidence of insect-punctured bolls (15 to 35%) and disease incidence (5 to 27%), than uninfested plants, when plants were infested for 72 h about wk 4 of bloom. Diseased bolls tested positive for bacterial contamination. From a pest management perspective, insect monitoring for verde plant bugs provided in-season indication of subsequent boll damage from cotton boll rot, and was especially relevant for cotton fields near coastal waters.