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Cockroach baits are widely accepted as one of the best methods for controlling cockroach problems, especially German cockroach infestations. A wide range of cockroach baits on the market are for professionals and DIY consumers, in a variety of formats – solid, gel and liquid. With many residents of government housing in the US having both ongoing cockroach problems, yet limited money to pay for professional pest extermination services, researchers in the US evaluated the performance of both consumer and professional cockroach baits.
The researchers selected three leading consumer cockroach baits of different formats – a solid bait, a gel and a liquid bait formulation – and three leading professional gel products from different manufacturers, using different active ingredients. The products were evaluated in laboratory trials, using both a susceptible lab strain and field-collected German cockroaches, and were also applied in real in-home situations.
In the laboratory trials it was perhaps not surprising that most of the products killed the susceptible cockroach strain quicker than the field-collected cockroaches. At the end of the 28-day trial, all but one product had achieved greater than 93% mortality. The only product that delivered significantly lower mortality compared to the other products, with a mortality of 84%, was the consumer solid gel bait.
However, it was interesting to note that the consumer liquid gel bait delivered significantly faster mortality than all other products, when mortality was assessed at the two-day reading, when it had already delivered 95% mortality.
In the field trial, the three professional gel products were applied to the same group of houses in a staggered application regime. The application of three different products, with different actives and different modes of action was expected to be the best case scenario for cockroach reduction. This was compared to the three different consumer baits which were applied in isolation. All products were placed as per the label – solid baits (18 bait stations), liquid baits (six bait stations) and gel baits placed as pea sized dots. Placements were focused on the kitchen, with additional placements in the bathroom and other hotspots as required. After the initial placement, baits were topped up as required at the two-week, one-month and two-month readings.
Professional gel baits delivered the best in-home performance, with the number of cockroaches trapped at the end of the trial down to a very low level. The consumer gel bait and consumer solid bait delivered significantly lower levels of control.
However, the surprising result was that the consumer liquid cockroach bait (0.05% dinotefuran) delivered a level of performance that was not significantly different to the professional gel products. This is despite there being only six placements (bait stations) compared with the multiple bait placements of the professional gel. The trial wasn’t set up to compare number of placements or amount of bait used, which could be investigated in further trials.
The researchers drew a number of conclusions from this work. Firstly, that laboratory studies do not necessarily give reliable indication as to how a product will perform in the field. Secondly, that two of the consumer products, even when placed by researchers, struggle to control cockroaches in a home situation. Thirdly, that the liquid consumer cockroach bait appears to be worthy of further investigation as an option for low-cost cockroach control in government housing. However, they do also note that in order to get good performance, correct product placement would be critical, along with educating residents on the other aspects of integrated pest management, especially cleaning regimes.
Further reading: Gordon, J.M et al. (2025). Laboratory and in-home evaluations of consumer- and professional-grade cockroach baits. Journal of Econ. Entomology. https://doi.org/10.1093/jee/toae291
