Roaches in Kitchen: Why They Show Up and How to Keep Them Out

TL;DR

• Take away their water, food and hiding places every day. Pesticides alone will not succeed (Health Canada).
• A clean kitchen is not automatically safe. Roaches can arrive on groceries, cardboard boxes or used appliances.
• Reduce water: fix leaky taps and pipes, don't leave water standing in the sink, and empty the drip pan under the fridge.
• Keep food in sealed plastic or glass containers, and try not to leave dirty dishes or pet food out overnight.
• Seal and caulk cracks, crevices and pipe openings, especially under the sink and around the stove and dishwasher (Health Canada).
• Need help? Get a quote from a recommended local exterminator through Pest Agent's referral form.

Flicking on the light at midnight and watching a few brown insects dart under the stove is how many people discover roaches in the kitchen. Health Canada notes that cockroaches are most active at night and may go unnoticed for some time, so the first one you see has rarely arrived alone.

Scrubbing the counters harder does not settle the problem on its own. A kitchen that looks spotless by day can still offer a slow drip under the sink, crumbs wedged in a cupboard crack and a warm, dark gap behind the fridge, and Health Canada says cockroaches will live anywhere food, water and shelter are available.

Why Are There Roaches in Your Kitchen?

Roaches in your kitchen are there because the kitchen gives them water, food and warm hiding spots in one room. Health Canada notes that cockroaches live wherever food, water and shelter are available, and that they are drawn to the warm, damp conditions of kitchens, bathrooms, basements and plumbing areas. They are most active at night, so you may not notice them for some time.

Water

Water is the first thing that draws cockroaches to a kitchen. According to UF/IFAS (University of Florida), water is often the most important factor in cockroach survival: German cockroaches tend to live much longer with water and no food than with food but no water. A dripping tap, a damp sponge, water standing in the sink, condensation on the pipes under the sink or the drip pan under the fridge can keep a whole colony alive.

Food Scraps

Food scraps keep roaches in your kitchen once they find water. Cockroaches prefer starches, sugars and protein but will eat almost anything when hungry (Health Canada). UC IPM (University of California) points out that even tiny amounts of crumbs or liquids caught in cracks are enough to feed them, and UF/IFAS notes that unwashed dishes can be a major source of food for a kitchen infestation. UF/IFAS also notes that the highest number of cockroaches in a home is often found around the garbage can and the refrigerator. Our guide on what attracts roaches covers the full list.

Warmth

Warmth is the third draw. German cockroaches prefer a moist environment with a relatively high degree of warmth, according to Penn State Extension, which is exactly what the space behind a fridge, under a stove or around a dishwasher offers. Appliances give off heat, and the voids around them stay dark and undisturbed.

Is a Clean Kitchen Safe From Roaches?

A clean kitchen is not automatically safe from roaches. Health Canada states that their presence does not necessarily mean conditions are unclean. Roaches and their egg cases can arrive on things you bring in: used furniture, food items, empty bottles and shipping cartons (Health Canada), infested grocery bags (UF/IFAS) or used appliances (Alberta Health). Cleaning makes it much harder for them to settle in, but it does not stop the first ones from arriving.

Which Cockroaches Show Up in Canadian Kitchens?

Cockroaches in kitchens in Canada are often German cockroaches, with Oriental and American cockroaches showing up less often, usually from basements or drains. The brown-banded cockroach also lives indoors in Canada, but UC IPM notes it is not usually associated with food preparation areas.

German Cockroaches

German cockroaches are the roaches you are most likely to find in a Canadian kitchen. Health Canada describes them as 1.3 to 1.6 cm long, tan to light brown, with two dark parallel streaks behind the head. They have wings but cannot fly. Penn State Extension notes they are usually found in kitchens near dishwashers, stoves and sinks. They breed fast: UC IPM states that a single female and her offspring can produce over 30,000 cockroaches in a year, which is why a few roaches can become a serious problem in a matter of months.

Oriental Cockroaches

Oriental cockroaches are larger and almost black. According to UC IPM, they tend to live in cool, dark, damp places such as basements and drains and may move indoors at night. In a kitchen, you are more likely to see one near a floor drain or coming from the basement than hiding in a cabinet.

American Cockroaches

American cockroaches are the largest, about 2 inches (about 5 cm) long and reddish brown. UC IPM describes them as common in sewers and storm drains and notes they can come up into buildings when pipes are damaged or drain water traps are faulty. If you see a big roach near the kitchen sink, read how to stop cockroaches from coming up the drain.

Where Do Cockroaches Hide in the Kitchen?

Cockroaches in the kitchen hide in tight, dark, warm cracks close to water and food, and come out at night. Alberta Health says they often spend the day in groups behind baseboards, in cracks and crevices in the kitchen, and under stoves, fridges and dishwashers. According to UC IPM, an adult German cockroach can hide in a crack only 1/16 inch wide (about 1.6 mm). Check these spots with a flashlight. For hiding places in the rest of the house, see how to find cockroaches.

Under the Sink

Under the sink is the top hiding spot for roaches in the kitchen because it combines water, darkness and gaps around the pipes. UF/IFAS lists pipe condensation under sinks as a possible moisture source. Look at the back of the cabinet where the pipes come through the wall.

Behind the Fridge

Behind the fridge is where roaches find warmth from the motor and water from the drip pan that catches condensation. UF/IFAS notes that cockroach numbers in a home are often highest around the refrigerator and the garbage can.

Under the Stove

Under the stove, grease and crumbs fall into a warm space you rarely clean. Alberta Health lists stoves among the places roaches hide during the day.

Around the Dishwasher

Around the dishwasher, heat and moisture make the gaps beside and under the unit an ideal hiding spot. Penn State Extension specifically names dishwashers, stoves and sinks as the usual places for German cockroaches.

Inside Cabinets

Inside cabinets, roaches hide in corners and in the gaps behind shelves, close to stored food. The Government of Manitoba suggests checking under sinks, beside the refrigerator and in closed cupboards.

Appliance Motors

Appliance motors can hide egg cases. UC IPM advises checking for egg cases in refrigerator and other appliance motors, as well as under furniture. This is also why a used appliance can bring roaches into a clean kitchen.

Sticky Traps

Sticky traps help you confirm where roaches are hiding and how many there are. UC IPM recommends placing them where floors meet walls and close to spots where you suspect roaches. Penn State Extension notes that a week of trapping usually gives enough information. Traps can show you where to focus, but they generally do not control an infestation on their own. If the traps fill up, read about the signs of a cockroach infestation.

How to Prevent Roaches in Your Kitchen

Preventing roaches in your kitchen means taking away their water, food and hiding places every day. Health Canada is clear that the living environment has to change first, because pesticides alone will not succeed. These habits are the core of how to prevent roaches in your kitchen. For the rest of your home, see our guides on how to prevent cockroaches and cockroaches in the bedroom.

Sealed Food Containers

Sealed food containers cut off the easiest food source. Health Canada recommends keeping food in tightly sealed plastic or glass containers. Move flour, sugar, cereal, rice, crackers and snacks out of paper bags and cardboard boxes once you open them.

Daily Kitchen Cleanup

Daily kitchen cleanup removes the crumbs and grease roaches live on. Clean up spills right away and do not let dirty dishes pile up, especially overnight (Health Canada). Wipe the counters and stovetop after meals, and it helps to empty the sink strainer often (UF/IFAS) and vacuum often, including behind appliances (Government of Manitoba). UF/IFAS adds that cockroach droppings contain a chemical that attracts other roaches, so wipe the areas where you found them with hot, soapy water.

Garbage

Garbage is one of the spots where roach numbers peak. Health Canada recommends storing garbage in sealed plastic containers and getting rid of it daily. Use a kitchen bin with a tight lid, and rinse it out when it gets sticky.

Pet Food

Pet food left out overnight is an open buffet. Health Canada advises against leaving pet food and water out 24 hours a day, and Alberta Health says not to leave pet food in the dish overnight. Pick up the bowls after meals and keep the bag in a sealed container.

Moisture Control

Moisture control takes away the water roaches need most. Repair leaky taps and pipes, and wrap or insulate pipes that sweat (Health Canada). Do not leave water standing in the sink, and it helps to empty the drip pan under the fridge (UF/IFAS) and dry the sink and sponges at night. A fan or dehumidifier can help if your kitchen stays damp.

Sealing Gaps

Sealing gaps removes the cracks roaches hide and travel in. Health Canada recommends sealing and caulking all cracks, crevices and pipe openings, and putting fine mesh screens over vents, open pipes and drains. Focus on the gaps where pipes enter the wall under the sink, along backsplashes and baseboards, and around the stove and dishwasher. UF/IFAS suggests that tightly packed steel wool may be used as a temporary filler for larger holes until they can be sealed properly.

Cardboard Boxes

Cardboard boxes give roaches shelter and a place to breed. UF/IFAS notes that cockroaches can breed prolifically in corrugated cardboard and suggests throwing out unnecessary boxes right away. Unpack groceries promptly, check deliveries before you put them away, and look over used appliances and furniture before bringing them inside, as Alberta Health recommends.

How Do You Get Rid of Cockroaches in the Kitchen?

Getting rid of cockroaches in the kitchen usually works best with daily cleanup plus many smaller baits (University of Kentucky), not sprays. Baits feed the roaches where they hide, while the habits above remove the food that competes with the bait.

Cockroach Baits

Cockroach baits are the safest and most effective option near food. UC IPM notes that insecticide sprays do not provide long-term control and recommends placing baits under appliances, along walls and in cabinets, which matches the hiding spots above. Health Canada notes that bait stations in tamper-proof containers kill cockroaches about 48 to 96 hours after they eat the active ingredient, and UC IPM warns that a bait program can take 7 days or longer to show results. Keep baits away from dishes, food and counters, and out of reach of children and pets. Before you buy, check that the label shows a PCP number, which means Health Canada registered the product, and follow the label. For tested products, see our picks for the best cockroach killer.

Dusts

Dusts reach the voids that baits cannot, such as the space under the stove and fridge or inside wall gaps. UC IPM notes that boric acid dust is not repellent and keeps working for a long time if it stays dry and undisturbed, but in Canada it is now registered only for professional use. Health Canada says diatomaceous earth is non-toxic to humans and pets, but you should avoid breathing the dust when applying it. Apply dusts only in hidden cracks and voids as the label directs, never on counters or where food is prepared.

Why Sprays Backfire

Sprays backfire in the kitchen because they rarely reach the roaches hiding in cracks. UC IPM notes that sprays may repel cockroaches and push them to other areas, and that foggers and bombs often do not reach the crevices where roaches breed. Penn State Extension adds that sprays and foggers inside a home are of little value and can scatter the roaches.

Why Home Remedies Fall Short

Home remedies such as vinegar, lemon juice, cinnamon, bay leaves and essential oils fall short because none of them removes the water, food and shelter that keep roaches in your kitchen. Health Canada and university extension guides focus on cleanup, sealing and baits, and do not list these remedies as a way to control cockroaches. If you want to try them anyway, our guide to cockroach repellents explains what to expect.

Insecticide Chalk

Insecticide chalk should never be used in your kitchen. Health Canada warns Canadians not to buy products sold as "Miraculous Insecticide Chalk" or "Cockroach Chalk": they are not registered in Canada, contain a pesticide that can cause serious health effects, and children can mistake them for ordinary chalk. If you have some, seal it in a plastic bag and take it to a hazardous waste collection site. Use only products registered for use in Canada.

When to Call a Pest Control Professional

Calling a pest control professional makes sense when you see roaches during the day, when sticky traps keep filling up after a few weeks of baiting and cleanup, or when you live in an apartment building. The Government of Manitoba notes that store-bought chemicals can be dangerous if used the wrong way and may spread roaches to other units, while licensed professionals can apply products not sold to the public. A professional treatment usually starts with an inspection to identify the species and hiding spots, followed by baits, dusts or targeted treatments and follow-up visits. If you rent, tell your landlord right away: in Manitoba, landlords are generally responsible for pest-free units once told, and Alberta Health says landlords must by law keep the home pest-free. Before a visit, read how to prepare for a cockroach treatment, since kitchen cupboards usually need to be emptied. You can get a quote from a recommended local exterminator through Pest Agent's referral form.