Adult German cockroaches are 1/2 to 5/8 inch long and tan to light brown.  Although they have fully developed wings, they do not fly.  Nymphs are similar in appearance to adults except that they are smaller and lack wings.  The German cockroach is best identified by its small size and by two dark parallel lines running from the back of the head to the wings.  It is usually found in kitchens (near dishwashers, stoves, and sinks) and in bathrooms of homes.

German cockroaches usually prefer a moist environment with a relatively high degree of warmth.  The insects are mostly scavengers and will feed on a wide variety of foods.  They are especially fond of starches, sweets, grease, and meat products.  In many locations, garbage is a principal food source.  As with other species, German cockroaches are mostly active at night, when they forage for food, water, and mates.  During the day they hide in cracks and crevices and other dark sites that provide a warm and humid environment.  Their relatively wide, flat bodies enable them to move in and out of cracks and narrow openings with ease.  They may be seen during the daytime, particularly if a heavy population is present or if there is some other stress, such as a lack of food or water or an application of pesticides.

The German cockroach is the most successful of the species infesting buildings.  There are several reasons for this cockroach’s persistence and the difficulty of controlling it.  German cockroaches produce a larger number of eggs per capsule and they undergo the shortest time from hatching until sexual maturity, resulting in a rapid population growth.  A greater number of nymphs hatch successfully because the female carries the egg capsule during the entire time the embryos are developing within the eggs.  Also, and most importantly, German cockroaches are smaller than most other cockroaches and can conceal themselves in many places inaccessible to individuals of the larger species.

Prevention Tips

German cockroaches are generally an inside pest.  Sanitation is the key to control.

Seal openings or cracks around exterior of home with putty or caulking.

Inspect sacks, cartons and boxes, etc., brought into the home and destroy any roaches.

Clean up spilled foods and liquids.

Avoid leaving scraps of food on unwashed dishes and counter tops.

Rinse cans and bottles before putting in trash and transfer garbage outdoors into roach-proof receptacles.