How Fast do Roaches Spread? Short answer FAST!

By kulmalukko - Own work, CC BY-SA 3.0,

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Many of us at least once in life have faced such a problem, as cockroaches. And if you met them before, you know how difficult it is to get rid of these bugs. But if it’s your first time, you probably have many questions. What are cockroaches? How fast do roaches spread? How to get rid of them? In this article, we will tell everything about your enemy.

How fast do roaches spread?

Cockroaches are one of the most rapidly breeding home parasites. If a pregnant female appeared in the house, the arrival of an enormous population becomes unavoidable. If the insects feel comfortable in the new place, and they have something to eat and to drink, the cockroaches spread at an unimaginable speed. If you have seen several pests in your kitchen or wherever else, then you will have about twenty times more cockroaches in 8 weeks. It depends on the type of bugs.

How can you understand that it is a roach?

To understand that a cockroach ran past you, and not some other parasite, you should check its appearance. The main features of roaches are:

  • The flat elongated body of oval shape;
  • The flat head is triangular;
  • Gnawing mouth turned down;
  • Mostly black or red.

Cockroach breeding cycle

To better understand your future enemies, you should know how do they reproduce. Let’s start from the three most common types of roaches – American, red and black.

  • The American cockroach is about two inches long, red-orange with dark horizontal lines on the back. It has a very elongated body shape, and lives mainly in the United States, but sometimes in Europe.
  • Black cockroaches reach 1-1.5 inches in length. Of the parasites living at home, they are the largest. Most often, they live and breed in kitchens, which is why they are sometimes called kitchen cockroaches.
  • But the most unpleasant are small red (or German) cockroaches that can fit into any gap. They are about half the size of blacks, but this is their main advantage. Due to its size, a larger population of red cockroaches needs less space. Red cockroaches can breed twice as much.

How fast do cockroaches reproduce?

By Fichbio - Own work, CC BY 4.0,

Cockroaches reproduce sexually, like any other animal. The breeding process begins with mating games, after which the male and female mate. The female seduces the cockroach, sometimes spreading its wings, and he impregnates it. But some individuals, like Madagascar hissing cockroaches, can also fight for the right to fertilize a female.

In general, Madagascar cockroaches are much more developed than those that are called pests and bother ordinary people. They tend to care for their offspring; they are not parasites and live quite a long time if they do not become a predator’s prey. After one mating session, the female, even without the male, will be able to fertilize several more times.

The process of reproduction and development of small cockroaches is as follows:

  • Females lay eggs in specific leathery bags – oothecae. Red and black cockroaches carry eggs with them, while other individuals prefer to hide them in secluded places;
  • An ootheca is formed only during the period of laying cockroach eggs. Its formation begins in the chamber under the abdomen. The female secretes a specific sticky substance, which wraps the eggs and keeps them safe throughout the entire growth period;
  • The formed embryos hatch from the leathery sacs 2-3 weeks after laying;
  • Larvae develop and change several times. Biologists name them nymphs; they look like miniature adults.
  • Large adults are forming;
  • In one egg, the female black cockroach carries 10-20 larvae, and the female red – 20-30.

At one time, the female can produce up to forty new embryos. As much as there will be enough to develop a population that will soon take over your home.

All this talk of cockroach reproduction may have you wondering where exactly cockroaches lay their eggs when they reproduce… find out here: Where Do Cockroaches Lay Their Eggs?

Features of reproduction

A female cockroach in its life can release 4-6 capsules before dying. For this, it does not need to mate each time; the male gametes remain in her body. Cockroaches settle in colonies; newborns live with adults. Several females look after small embryos and help them adapt and learn to survive.

Cockroaches do not have specific seasons when they breed.

The process continues year-round, which may complicate the fight against them. If you miss the moment when they just appeared at your place, the population will grow instantly. You need to fight them with all possible means from the very beginning.

How fast do cockroaches grow?

But how fast do cockroaches grow? Extremely fast. A roach can get up to 20-30 individuals from one egg, which allows achieving quite substantial results for the short active life. In four months, the female will thoroughly prepare the offspring for hatching. As a rule, the birth rate depends on many factors.

For example, the food and water availability on the inhabited territory, as well as temperature and humidity, decide on the population. In the most favorable conditions, the female can finish reproduction in 30 days. The speed of growth increases rapidly due to extremely humid and high temperature.

  • Favorable temperature: 30º (85º F) – offspring are growing fast.
  • Unfavorable temperature: 15 (60º F) – the growth process slows down. When the temperature drops, it stops.

The cockroach development rate is high, but its fertility is even higher. One individual of a red cockroach in its life can produce up to 8-10 eggs, of which more than 260 new individuals emerge. Of course, everything depends on living circumstances and room temperature. If the conditions of their habitat are not the best, then the average female produces about 2-4 oothecae in life.

However, the female is not alone, and the number of eggs depends on the capabilities. Often the cockroach population is limited by themselves using natural things such as hunger and competition. The number of cockroaches will not increase more than the premises allow. But they can relocate if the colony expands. Often, the growth of the roach society is the reason why they flee from neighbours.

The average population of home cockroaches can occupy the full living space in a month. Also, these bugs can quickly recover after the destruction. The ootheca is an excellent way to protect offspring from poison. So when all sexually mature individuals die, the new roaches hatch in a month. By analogy with bedbugs, which also lay eggs in a secluded place, cockroaches often survive the careless processing from unprofessional specialists.

How fast do cockroaches run?

The world’s fastest land insects are some big tropical cockroaches of the Dictyoptera family. In 1991, during an experiment, an American cockroach (Periplaneta americana) set a speed record of 5.4 km/h or 3.2 mph. It covered a distance 50 times the length of its own body in one second. For a human sprinter, this would correspond to a speed of 330 km/h or 205 mph. So it is not so easy to kill it.

 How long do cockroaches live?

The life expectancy of each type of cockroach varies, as they live in different conditions:

  • Red cockroaches that do not feel the need for food and live at optimal temperatures live on average 20-30 weeks and even one year. How long do cockroaches live without food? If food is missing for more than 40 days, then they die. The same outcome awaits them at low air temperatures.
  • The life expectancy of black and American cockroaches is higher than that of red ones. So, in comfortable conditions, they live for about two years, and without food – more than 70 days. Black cockroaches feel happy in moisture, so if you leave them without access to water, they will die within a week.

If you want to ensure that you’re not creating a hospitable environment for cockroaches to live in, you may want to learn what they like to eat. Try reading our article What Do Cockroaches Eat? to find out more.

How fast do cockroaches eggs hatch?

By Toby Hudson - Own work, CC BY-SA 3.0,

As we have said before, everything depends on the circumstances. It takes about 2-3 weeks for cockroaches eggs to hatch. So it is often hard to kill all the bugs in one attempt. Professional specialists repeat the roaches’ destruction in two weeks after the first procedure. Only this can guarantee the success of the mission.

Which cockroaches spread the fastest?

It is hard to say which kind of cockroaches spread the fastest. Some sources say that the Panclora roaches spread the fastest, but they are not common in the USA or Europe. Among the three most common species, the red cockroaches spread the most active. They reproduce two times more individuals than blacks and American at the same time. And these insects are not so requirable to the environment. They do not need water and are smaller than other species.


If you have seen a cockroach in your kitchen, do not ignore it. As you can see, these insects spread very rapidly. Few individuals will breed hundreds of others, and if you don’t fight them, the roaches will occupy your entire place. It is not the best feeling when you wake up and see cockroaches above your head. Or you want to heat your pizza in the microwave oven, and instead of cheese, you get bugs on it. We hope our article helped you to get enough information about this annoying insect, and you will fight all of them.

If you enjoyed reading this article, why not check out our articles on The Cutest Bugs in the World – With Pictures and What is the Rarest Bug in the World?

Steve Foster

Mad about bugs and wanting to publish as many articles as I can to help educate people about these amazing beautiful creatures! For more info check out my about page

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