Cockroaches are one of the most reviled of household pests and are difficult to control due to their habit of laying egg pouches containing many eggs in inaccessible places.
There are two common cockroaches found in the UK, the German cockroach and the Oriental cockroach. The four keys to effective cockroach control are hygiene, control, proofing and monitoring.
Residual insecticide sprays leave a thin film of toxic deposit on surfaces and will kill cockroaches for a limited period of time, usually about two weeks before a fresh application is required. Apply to cracks and crevices where cockroaches hide and move around, like under cabinets, etc.
Non-residual insecticide spray kills on contact only, very limited or zero residual effectiveness depending on product. However, most contain pyrethrins which, whilst lethal to cockroaches, also act as a flushing agent, exciting the cockroach which then rapidly leaves it's hiding place.
Insecticide Dust can penetrate cockroach hiding areas that other insecticides cannot reach. When applied to dry locations they have a longer useful life than residual sprays. Some dusts contain insecticide and others contain no organic chemicals and act by rubbing off the protective waxes that cover the cockroaches body, causing death by dehydration. Apply into dry cracks and crevices, under and behind cupboards where they may be active. Dusts can be used with great effect in areas where sprays could not be used, such as in and around electrical appliances.
Poison Baits can be applied in areas where it may not be acceptable to use insecticidal sprays; for instance in kitchens where children and pets have access. In such situations Gel Baits can be applied to surfaces providing there is no risk to non target species.
Monitor with sticky cockroach traps, and inspect them regularly to detect any new infestations before they become a real problem.
The two principle species encountered in Britain are:
German Cockroach life cycle:
Oriental Cockroach life cycle:
Cockroaches are common in commercial premises and are associated with food production and handling. They are also common in public buildings and residential units such as blocks of apartments.
Both species are gregarious and nocturnal. They spend daylight hours hiding in cracks and crevices around areas such as kitchen sinks, cookers, refrigerators, drains and cupboards. They especially favour large building complexes with interconnecting ducts and plumbing systems.
Cockroaches need food, water and shelter to survive. Water is particularly important which is why they are so often found in kitchens and bathrooms.
German Cockroach preferred habitat:
Oriental Cockroach preferred habitat: