Cockroaches are an extremely common household pest throughout all of New Zealand and although they make you shudder when you see them, they thankfully do not pose many health risks, however they can transmit diseases, so it is best to keep them out of your home. As with any pest the number one preventative measure is to keep your home and outside surrounding areas as clean as possible. We’ll talk through more information about the different types of cockroaches, how to prevent an infestation before it happens, and if needed how to kill cockroaches. 

What are the 3 main types of cockroach?

Although there are thousands of different species of cockroach, here in New Zealand we tend to only deal with the following three culprits. They are all pests and have the potential to transmit diseases such as dysentery, salmonella and diarrhoea due to their eating habits. See below for more information on the pests most wanted list.

The Gisborne Cockroach

This is our native representative, although it was first introduced from Australia, they are usually not found in doors at all so if you spot one of these in your home, it was likely by accident such as being carried in through timber and firewood. 

They commonly live outdoors in damp dark areas and feed on decaying forest matter, so if you happen to spot one of these, it might be worth just giving a helping hand to get it back outside again.

The American Cockroach

This is the most common species found in New Zealand and is known as a pest throughout the world. Despite the name this species is native to Africa and the Middle East. They have adapted very well to human living spaces as they prefer moist areas with warmer temperatures. 

Classified as omnivores, they will eat many foods as well as materials including leather, beer, glue and book bindings. They have the potential to cause sickness in humans, from their odorous secretions and bacteria that they pick up and deposit on food and surface areas and so it is very important to keep your house as clean as possible.

The German Cockroach

Although the smallest of the cockroach species found in New Zealand, they are actually the biggest problem. They do not like cold temperatures to a point where they struggle to survive and so they will always look to go inside of buildings for warmth. They more commonly prefer restaurants, food processing facilities and hotels to residential.

They are defined as omnivore scavengers, meaning they eat everything the American Cockroach does as well as meats, starches, sugars and fatty foods.

Did you know: Cockroaches are actually incredibly old with evidence suggesting they have been around for over 300 million years. That puts them all the way back in the days of dinosaurs!

What is the standard lifecycle of a cockroach?

Cockroaches have three distinctive stages, those being egg, nymph and finally adult. This can take between a few weeks and a year to complete all stages depending on the cockroach species, conditions and overall process.

Adult females can lay anything between 5-30 egg sacs that can contain 12-40 cockroach eggs, this can make it particularly hard when trying to remove them as an infestation can happen very quickly.

How to prevent cockroaches from entering my home?

The question everyone wants to know is, now that you’ve spotted one of the above offenders scurrying around your home, how do you get rid of it and stop any more attempted breaches of your home’s border? 

  • Keep all inside areas dry and clean, especially living areas and kitchens where food is handled 
  • Dispose of rubbish, human & food waste often by sealing it in a bag and taking it to the outside garbage bins
  • Keep food stored in sealable containers and store in hard to access places 
  • Lastly, look around the inside and outside of your home and where necessary fill in any cracks or gaps in walls, ceilings/roof, floors/foundations etc.

How to remove a cockroach infestation?

So you have taken all of the preventative measures and now you either suspect or know that you have an infestation. Visit your local supermarket or hardware store and purchase some roach traps.

Roach traps are one of the easiest and most effective ways to get rid of roaches. Most of these devices feature bait or a type of attractant that lures the pests and adhesive that prevents them from moving when coming into contact with the trap. Location is key with a cockroach bait trap. Underneath kitchen appliances and in cupboards, bathrooms, and basements are all good choices.

You could also try store bought baits, these are chemical disguised as food that will kill any cockroach that ingests it.

Home remedies you could and should not try.

You’d be surprised how many hints, tips and tricks are out there, here we will let you know which ones work and which ones do not.

  • Sugar & Baking Soda – this is a nice home strategy, sugar attracts cockroaches & then baking soda destroys their digestive system
  • Insecticides such as Boric Acid (Takes 3 days) (works best when applied to areas where cockroaches hide during day or pass through at night)
  • Lavender, lemon citrus, eucalyptus and white vinegar will all deter cockroaches but will not kill them.

Do not step on a cockroach, this will not spread their eggs, however it might bring others out to feed because they do have cannibalistic tendencies.

Thanks to Jae Services for writing this.