German Cockroaches: How to Get Rid of Them at Home

German cockroaches are the small, light-brown ones with two dark stripes behind the head. They live entirely indoors, mostly in a warm kitchen, and breed fast. Spraying the ones you see leaves the egg cases and most of the population untouched. Leave no food or water out overnight, seal the gaps, put many small dots of bait where they shelter, and count what the sticky traps catch each week. If nymphs are still turning up three to four weeks later, have the home surveyed.

How do I tell German cockroaches from the large ones?

Size and markings settle it. The large cockroach also seen in Ho Chi Minh City homes is the American cockroach. The figures below come from the integrated pest management programme of the University of California (UC IPM).

A small cockroach about as long as a finger joint, running fast around the kitchen, is a German cockroach or the young of a larger species; two dark stripes on its back make it almost certainly German.

Feature	German cockroach and American cockroach
Length	German: about 1.3 cm. American: about 5 cm.
Colour and markings	German: light brown, with two dark parallel stripes on the shield behind the head. American: reddish brown, with a pale rim to that shield.
Where it lives	German: wholly indoors, mostly in the kitchen cabinets, around the fridge and microwave, and in the bathroom. American: hot, damp places such as sewers, drain pits and service ducts.
How it gets in	German: it lives and breeds inside the home. American: up through floor drains, damaged pipes and gaps under doors.
Young (nymphs)	Wingless, small and darker than the adults. American nymphs are small too, but darker than German ones, and they keep to the drains.

Why are German cockroaches so hard to get rid of?

They breed fast and keep their eggs out of reach. A cockroach passes through three stages: the egg, held in a hard brown case shaped like a bean; the nymph, which sheds its skin several times; and the adult. According to UC IPM, one German cockroach egg case holds about 30 young, and the female carries it with her until shortly before it hatches. She can form a new case every few weeks, so it takes only a handful of survivors to restore the numbers.

Nymphs eat the same food and shelter in the same crevices as the adults. Many small cockroaches seen by day mean a large population breeding inside the home, and cockroaches in the open in daylight usually mean the hiding places are full.

Where do German cockroaches hide, and how do I find them?

They choose narrow gaps that are dark, warm and close to water. Because they come out at night, traces usually show first: droppings like ground black pepper in drawer corners, on hinges and behind appliances, shed skins, dark speckled stains and, once there are many, a musty smell.

Go round with a torch and note every place with droppings; those are the points for bait and traps later. For a rough count, leave sticky traps overnight below the sink and at the back of the fridge, or turn the kitchen light on without warning after midnight.

Place	Where exactly to look
Kitchen cabinets	Hinges, joints, inside corners and undersides; the backs of drawers; spice racks and the rice bin; the gap between cabinet and wall, especially behind a dishwasher or built-in oven.
Appliances	Behind and beneath the fridge, its motor compartment and door seal; the backs of the microwave, rice cooker and coffee machine.
Sink	Underneath, around the waste pipe and at the point where pipes pass through the cabinet panel.
Drains and ducts	Floor drains in the kitchen, bathroom and laundry balcony; service ducts; the refuse-chute door; sockets and recessed lights near the kitchen.
Stored paper	Cardboard boxes, newspapers and old plastic bags kept in a storeroom or under the stairs.

Why does spraying alone not get rid of them?

An aerosol kills mainly the insects it hits. The eggs are protected inside their case, and the bulk of the colony sits far back in the joints of the cabinets. While food, water and shelter remain, the next nymphs to hatch fill the gap. UC IPM's guidance stresses the point: pesticide used alone will not solve a cockroach problem, and sanitation is the foundation.

Spray also works against bait. Its smell makes cockroaches avoid a baited spot, so never spray on or beside one. For safety, do not use an aerosol near a lit hob, near food or in a closed room with people in it; anyone with asthma or allergies, and pregnant women, should stay away from an area that has just been treated with chemicals.

How do I cut off their food and water?

Leave nothing out overnight. A cockroach can live on crumbs and a few drops of standing water.

Before bed, wash the sink and wipe the hob dry; no dirty dishes stay out until morning.
Keep rice, cereals, sugar, sweets and pet food in containers with tight lids.
Empty the rubbish each evening, use a bin with a lid and wash the bin regularly.
Wipe grease off the kitchen wall, the extractor hood and the sides of the hob.
Repair dripping taps and leaking waste pipes, and dry the drip tray under the fridge.
Throw out spare cardboard and old paper. Cockroaches readily nest in the folds of cardboard.

How should I place cockroach bait, and how do I know it is working?

Gel bait and bait stations generally suit an occupied home better than spraying a wide area, because cockroaches feed on the bait and then go back to where they shelter. UC IPM points out that cockroaches are not lured to bait from far off, which is why it must sit right beside their hiding places and routes.

Choose only a product with a registration number issued by Vietnam's Ministry of Health, and follow its label on placement and quantity.
Put down many small dots: in cabinet corners, on hinges, under the sink, behind the fridge and wherever you recorded droppings.
Keep bait where children and pets cannot reach it, such as the inner side of a cabinet hinge or the gap behind an appliance, and never on a surface where food is prepared.
Do not mix products, and do not decant any of them into a drinks bottle.
Leave sticky traps at the same checkpoints and count the catch each week. A count that falls week after week shows the bait is doing its work. Wash your hands after handling bait or dead cockroaches.

How long does it take to get rid of German cockroaches?

Plan on several weeks. Even a thorough round hardly reaches the egg cases held in the cabinet joints, so cleaning and baiting continue while those hatch. A weekly note of the trap count shows when the population has really fallen.

Clean up as you go. According to the US Environmental Protection Agency (EPA), allergens from cockroaches can set off asthma attacks, in children above all, which makes removing droppings and dead cockroaches as important as killing the live ones. Put on gloves and a mask to empty a cupboard with many droppings, and wipe damp or vacuum instead of sweeping dry.

When	What to do
Week 1	Clear out and clean, seal the gaps, and set bait and monitoring traps at the points you recorded.
Weeks 2 to 4	Check the bait every few days and replace what has been eaten. Collect egg cases and dead cockroaches as you find them.
From week 5	If the traps catch almost nothing, check less often, but keep up the habit of cleaning the kitchen cabinets.

Why do cockroaches keep coming into an apartment, and which gaps should I seal?

In a high-rise, service ducts, refuse chutes and pipework are shared between floors, and cockroaches travel along them from one flat to the next. A clean flat can still get them when the flat next door or a common area has them. They also arrive in cardboard boxes, shopping bags and second-hand appliances. Engineered-board cabinets with many joints, built-in appliances that give off heat and a sink that is always damp then provide the shelter they look for.

If the neighbours have cockroaches too, agree with the landlord or building management to treat at the same time. In your own flat:

Fill the gaps around water pipes and electrical conduits where they pass through walls and cabinet panels, using silicone sealant.
Fit floor drains with a mesh or anti-backflow cover. Cover seldom-used drains at night, and pour water into them from time to time so that the trap stays full.
Fit a seal along the bottom of doors, and close the gap between frame and wall at the door to the laundry balcony.
Look through delivery boxes and bags brought in from outside before they go into a cupboard.

When should I call pest control for German cockroaches?

Doing it yourself is usually enough when a few cockroaches turn up in one area. Call a provider when nymphs are still about after three to four weeks, when you find egg cases or see cockroaches by day, when they are in several rooms, or when they return after several attempts of your own; also when a household with small children or someone with a respiratory illness wants to limit its own use of chemicals.

German cockroaches that have spread widely usually need gel bait in the kitchen cabinets, residual treatment in damp areas and follow-up checks. Gel bait has little odour and needs no wide spraying, so the household usually keeps out of the area only briefly; clear results take a few weeks.

What UpClean does about German cockroaches, and how to book a survey

UpClean starts with a free survey of the cabinets, the spaces around appliances, the service ducts and the floor drains, to name the species and find where it shelters. A written, all-inclusive quote follows, with the method, how long to keep out of the kitchen and the number of follow-up checks. In an apartment, points in common areas are marked for you to raise with building management.

Before treatment an Up specialist, one of UpClean's identity-verified and trained staff, deep-cleans the kitchen, down to the grease and crumbs inside the cupboards and under the fridge and sink, so that the bait has no easier food to compete with, and puts away food, dishes, children's things and pet bowls. UpClean's own pest-control technicians then place gel bait and treat the hiding places with products that hold a valid registration number in Vietnam. Food-contact surfaces are wiped afterwards, and the bait points are left untouched. UpClean has declared its eligibility to provide pest-control services as required by regulation; the declaration and product information are available on request.

The Up Report, sent by WhatsApp or Zalo after each visit, shows where bait was placed, before-and-after photos and the dates on which the technicians return to inspect and add bait. To arrange a survey, send photos of the cockroaches, their droppings or the place you see them to 0968 726 135 on WhatsApp or Zalo, any day between 7:00 AM and 8:00 PM. Enquiries, the written quote and the report are available in English. The specialist's name and photo are sent beforehand, for buildings where residents must register outside staff with management.

Cockroach control: Scope of the service and the areas covered.
Cockroaches, ants and geckos in Saigon apartments: The wider picture, including ants and the geckos that feed on small cockroaches.
Fridge and cooker-hood cleaning: Can go into the same quote as a cockroach treatment.
Book a survey: Send the request online.

Frequently asked questions

What do cockroach eggs look like, and does spray kill them?+

The eggs are enclosed in a hard brown case, shaped like a bean, that protects them fairly well. Vacuum up or collect any case you find, and keep bait down for a few weeks to deal with the nymphs that hatch.

Are cockroach droppings dangerous?+

Droppings, dead cockroaches and shed skins contain allergens that can make asthma worse. Wipe them up damp or use a vacuum cleaner with a good filter, wear gloves and a mask, and do not sweep dry, which raises dust.

Is cockroach bait safe to use with small children and pets at home?+

Yes, provided the product carries a Ministry of Health registration number, you read the label, and you place it where children and pets cannot reach. If in doubt, ask an eligible provider to advise on the method.

I see more cockroaches since the gel bait was put down. Is that normal?+

It can be. With gel bait the numbers fall gradually over a few weeks, not on the first day, and at first more cockroaches may come out into view. The technicians assess and add bait at the follow-up checks.

Can I wipe the kitchen after a cockroach treatment?+

Wipe the food-contact surfaces, such as the worktop, the dining table and the dish rack, as instructed. Do not wipe or use cleaning sprays on the hinges, cracks and undersides of shelves where bait was placed.

How much does cockroach control cost in Ho Chi Minh City?+

UpClean lists no rate, because each kitchen needs its own plan. The written, all-inclusive quote follows a free survey and depends on the species and its spread, the type of home and the rooms to treat, the method, the follow-up checks and the kitchen cleaning involved.

German cockroaches: how to identify them, why sprays fail, and how to get rid of them