In the kitchen
How to Get Rid of Cockroaches in the Kitchen
Every warm void in a kitchen is a potential address, and most of them are inside appliances. This is where to look, what to change, and where bait can safely go in a room where food is prepared.
Under the sink, behind the kickboard, inside the hinge. That is the whole search.
A kitchen gives an insect everything at once: heat that never switches off, water within a short walk, food in a hundred small quantities and gaps of exactly the right width. So the real question of how to get rid of cockroaches in kitchens is a search problem, not a shopping problem. Find the voids and the rest follows.
This one stays room-specific. It maps the hiding places in a typical Melbourne kitchen, opens up the appliances that hold most of a population, says where bait can go around food, and separates the cleaning that helps from the cleaning that only tires you out. Tim's other guides to dealing with pests yourself cover the rest of the house.
One thing to accept first. Wiping benches harder will not do it, because the population is not on any surface you can see. That misunderstanding is the usual reason a determined effort gets nowhere.
The map
Why does a kitchen suit them better than any other room?
Because it is the only room that supplies warmth, water, food and narrow gaps in the same square metre. Take away one of those and a cockroach moves on. A kitchen offers all four permanently, and the appliances in it run at a steady temperature day and night, which no other part of a house does.
Motors and insulation hold a handful of spaces mild all year, whatever the weather outside is doing.
A weeping tap, a damp cabinet base or a drip tray matters more than crumbs ever will.
A hinge pocket, a drawer runner and the dead space behind a kickboard are the right width exactly.
- Why a gap beats a cupboard shelf
- Cockroaches settle where something touches their back and their belly at the same time. An open shelf fails that test and a hinge pocket passes it, which is why a cupboard can look empty while the door it hangs on is full.
The cabinet under the sink is the busiest address in most kitchens, and plumbing is the reason. Wherever a waste pipe or water line passes through the base or the back panel there is a hole cut larger than the pipe, leading into the cavity under the floor. Nobody seals them, nobody looks at them, and they are shelter and road in one.
- The collar where the waste pipe drops through the cabinet floor, usually a ragged hole with a gap all round it.
- The holes for the hot and cold tap lines, and the cut-out behind a dishwasher for its hose and power lead.
- The void behind the kickboard, which runs the length of the cabinetry and connects every cupboard above it.
- The hinge pocket of each cupboard door, the back upper corners of cupboards, and the runners under drawers.
- The hollow behind a switch plate or power outlet, the space behind a splashback, and the open end of a benchtop run.
Sealing those collars, with steel wool packed in behind the sealant, is the piece of kitchen work that keeps paying. It removes shelter and closes the route between your cupboards and the subfloor, which matters most in older weatherboard homes around Melbourne.
Open them up
What is living behind the fridge and inside the dishwasher?
More of the population than everything on your shelves put together. The motor housing at the back of a fridge, the lining inside a dishwasher door and the recess that machine slides into stay warm, dry and undisturbed, which is precisely what a cockroach is after. Nothing applied to a cupboard interior reaches any of them.
Look at the motor housing low at the back, the drip tray above it, the coils and the floor beneath. Unplug first. Warmest, driest and least disturbed spot in the room.
The insulation inside the door panel, the rubber channel round it, the sump area and the cabinet recess the machine slides into. Warm and damp together, and the electronics are a genuine casualty.
The hollow base of a cordless kettle, the crumb tray of a toaster, a coffee machine drip tray and the vent slots of a microwave. These get carried around the house, which is how other rooms join in.
The trim round an oven door, the slots either side of a freestanding cooker, the rangehood filter housing and the void behind a wall oven. Grease plus warmth is the strongest draw there is.
Checking these is a half hour with a torch and a mirror. Unplug, pull the machine clear, look low and into every vent, and photograph what you find so you can compare it in a fortnight. Black specks the size of a pinhead at the edge of a housing mean the spot is live.
Never spray into an appliance: liquid and electrics are a bad combination, insecticide on a heating element is worse, and the insects are inside the housing where no droplet lands anyway. If an appliance is harbouring them, it needs a small amount of bait in the cool outer recess it sits in, not a wet cavity.
People do throw out a dishwasher or a microwave over this, and it is almost never needed. The machine is accommodation, not the cause, and a replacement fills up within weeks if nothing else changes. Second-hand whitegoods coming the other way are the real risk, since that is one of the surest ways a population moves house.
Where the bait goes
How to get rid of cockroaches in kitchens, placement by placement
Small spots of gel pushed deep inside the voids, many more of them than seems reasonable, and never on a surface that touches food. Placement decides the outcome far more than which product you buy, and a kitchen that gets four placements instead of forty is the usual reason a home attempt stalls.
| Location | Exactly where | Why there |
|---|---|---|
| Cupboard doors | Inside the hinge pocket, top and bottom, on every door | Enclosed, dark, and already the busiest resting spot in the room |
| Cupboard interiors | The two back upper corners, not the shelf itself | Out of reach of hands and food, and where they already rest |
| Drawers | Under the runners and along the side rails | A protected gap that is never wiped |
| Kickboard | Just inside the void, every metre or so along the run | The corridor that links every cupboard in the kitchen |
| Sink cabinet | Around the pipe collars and at the back corners of the base | Water, darkness and an opening to the cavity beyond |
| Appliance recesses | The cabinet space a dishwasher or fridge sits in, low and at the back | Reaches the void without putting anything inside the machine |
| Never | Benchtops, shelves, inside the fridge, near the kettle spout, open floor | Food contact surfaces, and open ground they cross rather than rest on |
Quantity is the thing people get wrong. A spot about the size of a lentil, several per cupboard rather than one per room, puts food within a short walk of every shelter. One large blob is a single destination most of them never find.
Safety here is mostly about position. Inside a hinge pocket or behind a kickboard, gel sits beyond the reach of a crawling child or a curious dog and well away from anything you eat off. On a bench it is unsafe and useless at once. Read the label first, since it sets the permitted places and rates.
Leave the placements alone: the fastest way to undo a fortnight of progress is a weekend clean with degreaser through the cupboard gaps. Wipe the shelves and the benches as usual, and do not touch the hinge pockets, the kickboard line or the appliance recesses until the problem is finished.
The useful cleaning
Which cleaning jobs actually reduce the shelter?
The jobs that take away water, grease and hiding places, in that order. A dry sink overnight and a mended tap beat an hour of bench wiping. Clearing the toaster tray, the kettle base and the rangehood filter removes the grease that holds them. Throwing out cardboard removes the shelter outright.
- Water offMend the weeping tap, leave the sink and rack dry overnight, take up the pet bowl.
- Grease outToaster crumb tray, kettle base, rangehood filter, the oven door trim and under the cooker.
- Card outFlatten and remove every box and paper bag the same day. The flutes are shelter and transport in one.
- Bin routineLidded bin, liner changed before it leaks, and the under-sink bin cleaned rather than just emptied.
The bin earns its own sentence. Keeping it under the sink parks food waste beside the wettest, darkest cabinet in the room. A sealing lid, a liner changed before it splits and a weekly wipe of the bin remove a supply no bait competes with.
Sealed containers matter less for your crumbs than for the bait. It needs to be the most tempting thing in that cupboard, so a split packet of sugar or a sticky jar lid beside a placement is quietly working against you.
Cardboard is the one item in a kitchen that is both a hiding place and a delivery service. Get it out the day it arrives.
None of this is a comment on your housekeeping. A brand new apartment still has hinge pockets, a warm fridge motor and a dishwasher recess, and the insects usually arrive in a carton or through a shared wall.
Where DIY ends
When does a kitchen problem stop being a DIY job?
Once small pale insects turn up in numbers, once tiny wingless young appear, once a second room joins in, or once three weeks of proper baiting changes nothing. Those four are the markers of a breeding indoor population, and clearing one calls for a growth regulator plus a return visit.
- Young in the kitchen. Anything smaller than a sesame seed is a nymph, so eggs are hatching in the room rather than insects visiting it.
- Daytime activity. Insects out in the open in daylight usually means the gaps are crowded.
- It reached the bathroom. A second room means they have divided, and one torch no longer covers the ground.
- Three weeks and nothing moved. You have either not found the shelters, or something repellent is keeping them off the gel.
One large dark insect at midnight is a different story and usually not a kitchen problem at all. Those arrive from a drain, a gully trap or a subfloor, and the fix is the water seal in the trap rather than bait in a cupboard. Both situations are set out in the main guide to clearing cockroaches.
If it is the small pale species, the treatment is a staged one and the detail is on German cockroach treatment in Melbourne. Tim turns up to every visit himself on Victorian licence No. 86488, is fully insured, settles the figure before starting, and gives the rooms he treats a re-treatment guarantee for three months. His service area is Melbourne plus the suburbs that surround it. Send a photo with your suburb for a quote before you decide anything.
Questions
Kitchen cockroach questions
Why do I only see them at night?
Because they avoid light and movement, and feed once the room goes quiet. Daylight sightings usually mean the gaps are crowded enough to push insects out into the open, which says the population has grown rather than being chance. A torch at two in the morning gives the honest picture.
How do I check behind the fridge?
Unplug it, pull it forward, then examine the motor housing low at the back, the drip tray above it and the floor beneath. A torch and a small mirror are enough. Fine black specks gathered at the edge of the housing tell you it is occupied even when nothing moves.
Is bait safe in a kitchen where food is prepared?
Yes, when position is respected. Small amounts go inside hinge pockets, behind the kickboard and in appliance recesses, never on a bench, a shelf or anything food touches. The label states where a registered product may be used, and sticking to it keeps the room safe.
Should I empty every cupboard before treating?
Not all of them. Open up the cupboard beneath the sink, move anything pressed up against the fridge or the dishwasher so the recesses behind them open up, and seal loose food. Emptying the whole kitchen onto the dining table mostly creates work and fresh hiding places.
Does a dishwasher kill them on a hot cycle?
No. The water and heat stay inside the wash chamber, while the insects shelter in the door lining, the outer casing and the cabinet recess, all of which stay comparatively cool. The hottest setting on the dial changes nothing about where they live.
Are they a food safety problem at home?
Worth treating as one. Cockroaches feed on rotting waste, and the Better Health Channel says they are believed to spread illnesses such as salmonella and gastroenteritis, with droppings and cast skins also tied to allergy. At home that means sealed containers, surfaces wiped before bed, and dealing with the population itself.
Cleared the cupboards and they are still coming out at night?
Tell Tim which appliances they appear from and how long it has run, and he will explain the treatment and the figure before anything is booked.
Reviewed October 2026 by Tim, licensed pest control operator (Victorian licence No. 86488). Cockroaches, harbourage and health: Better Health Channel. Registered products and label use: APVMA.