Cockroaches

A fully-grown cockroach has a flattened brown oval body with long spiny legs and measures 15mm (3/4") in length. Roaches can be brought into the home in the form of egg cases that have been laid in groceries, rugs, used appliances, etc. They are not always a sign of poor housekeeping.

Cockroaches thrive in areas where food, water, and shelter are readily available. They tend to live in darkened or damp areas such as around sinks, behind stoves and refrigerators, in drains and cracks. They are often only seen at night. Control of cockroaches can be difficult due to their long life cycle. Every 20 to 28 days, a female drops one to four egg cases (ootheca); each contains 35 to 50 nymphs. Over a period of 100 days, the nymphs reach the adult stage. Consequently any place infested with cockroaches will also be infested with their eggs. You cannot expect instant results.

Remove their sources of food and water

  • Store food in sealed, washable containers
  • Clean any food spills up as soon as they occur
  • Don't leave dirty dishes in the sink overnight; empty garbage containers daily and rinse out all recyclable items before putting them in the recycling bin
  • Thoroughly wet-mop floors and baseboards, especially under rugs, furniture, and behind appliances
  • Wash inside food storage cabinets and keep them clean
  • Vacuum regularly wherever crumbs or dry pet foods might fall
  • Repair any leaking taps or plumbing and empty pet water dishes nightly (refill in morning)

Block their points of entry and remove areas of shelter

  • Use a foam or silicone caulk to seal all holes in ceilings, floors and walls, particularly around water and drain pipes; a 2mm crack is all they need
  • Remove as much clutter as possible from your home. Don't keep cardboard boxes and paper bags as these are ideal breeding areas

Physical control

  • Use as many traps as possible to monitor the location of roaches in your home so you know where to concentrate your efforts. Place them under sinks and in the corners of rooms where roaches have been seen at night.
  • To prepare your own traps, darken the inside of a quart-sized mason jar by wrapping it in paper or painting the inside black; coat the inside of the jar with petroleum jelly to prevent the roaches from escaping. In the morning kill the roaches by drowning them in hot, soapy water and then place the dead insects in the garbage.
  • You can vacuum roaches. To ensure all roaches are destroyed, the vacuum bag should be immediately immersed in hot, soapy water or placed in a sealed plastic bag or container (with no holes in it) for disposal.

Kill those that remain

  • Place small piles (1/4 teaspoon each) of household borax powder in places where they will stay dry, but are out of the reach of children and pets, e.g. under the refrigerator.
  • Borax, diatomaceous earth or silica aerogel with an attractant added are commercially available - they are effective and non-toxic. (Note: Ultrasonic or "electronic" devices neither kill nor repel cockroaches).
  • Freeze bags of pet food or birdseed to eliminate any cockroaches in them
  • When the external temperature is minus 18oC (0oF), infested appliances or furniture should be left in the garage for several days, as the cold temperature will kill the roaches and their eggs.
  • Alternatively, you can use the services of a pest control contractor to control a cockroach infestation.

In an apartment building or other multi-unit dwelling, community effort is essential to ensure an effective cockroach management program.

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