When Do Stick Insects Reach Adulthood?

green stick insect sitting on leaves in a tree

When do stick insects reach adulthood? At first it appears a simple question, but the answer is actually not what most people expect.

In humans, for example, adulthood makes up the majority of our lives. The same goes for most other animals. But when it comes to stick insects, the answer is different. In a nutshell though…

Stick insects reach adulthood (maturity) after their final moult. Depending on the species in question, this could take anywhere from 3 months to over a year. Factors that influence this are the sex of the insect and the size of the species.

I am going to discuss the various growth stages of stick insects and reveal exactly why adulthood only makes up a small fraction of a stick insect’s overall lifespan.

 For more advice and information on keeping and looking after stick insects, check out my ebook on Amazon click hereOpens in a new tab. (opens in a new tab).  

Adulthood is a Minor Final Stage of Stick Insect Life 

The reality of the situation is that adulthood is the final growth stage for a stick insect. After your stick insect has moulted for the final time, it will only have a relatively short time left to live.

Stick insect spend most of their lives growingOpens in a new tab., so when they get to the final growth stage the end is, unfortunately, nigh. Nevertheless, how long stick insects live upon reaching adulthood depends entirely on the gender and the species.

For a start, females always tend to live longer than their male counterparts. Once a stick insect reaches adulthood, the average female will live on for about six months, but the average male may only live for a month or so.

Moreover, as stick insects can actually live up to a couple of years oOpens in a new tab.r so, it gives you an idea of how little adulthood truly matters in their world.

How Does Size and Species Impact the Lifespan of a Stick Insect? 

Size does matter to stick insects.

The larger a stick insect species is, the longer it is going to live. The Timema cristinaeOpens in a new tab. from North America grows to only a half-inch long, so it’s not going to live as long as other species.

However, the giant spiny stick insect is one of the biggest stick insects in the world, native to Papua New Guinea, and is about six or seven times the size of the Timema cristinae; it is also among the longest-lived stick insect species.

Even so, the largest influence on longevity is gender. Within any species of stick insect, the males will, on average, usually only last for about half as long as a female.

If you want to consider it in averages, the lifespan for a male stick insect is two years while a female will last for up to four years. Less than 20% of a female’s lifespan is as an adult.

Is a Stick Insect Always a Youngster? 

It is difficult to adjust your thinking on how you consider adulthood in stick insects if this is your first time caring for themOpens in a new tab..

Like most insects, most of their lives are spent as subadults. There are lots of scientific terms for the various growth stages, but there are only three you really need to know about: nymph, subadult, and adult.

Nymph – A stick insect is a nymph after hatchingOpens in a new tab. but before shedding their skin for the first time and moving onto the next growth stage. They are particularly vulnerable at this stage in their lives.

Subadult – This is the stage at which a stick insect lives the longest for. It is the gap between completing the first growth stage and their final moult. Each time they shed their skin, they will grow. You might even notice that your pet has doubled in size in the space of a few days.

The number of shedding phases within the subadult stage will depend on the species. On average, a stick insect will have between six and nine moulting stages. The larger the species, the more shedding stages it has.

Adult – An adult stick insect has shed its skin for the final time and has reached full size. These are the last months of a stick insect’s life.

Can You Influence the Lifespan of a Stick Insect? 

A healthy stick insect kept in a clean environment with plenty of food is unlikely to fall ill due to a fungal infection. However, stick insects are extremely sensitive to temperature.

It is because of this vulnerability that you will find exotic stick insect owners utilising things such as heat mats and heat lamps to better recreate their particular species’ natural environment. Using a heat source has an effect on stick insectsOpens in a new tab. in how they grow.

The main reason temperature needs to be kept at a certain level is that this influences humidity. Preparing to shed its skin means that stick insects are about to go through a stressful process. A lack of humidity can make it almost impossible for them to effectively shed their skin. Some stick insect even lose body parts if the humidity levels aren’t high enough.

This is the reason that many stick insect guides remind you to mist your stick insects when they are about to moult. It helps make the outer layer of skin suppler and easier to remove.

Another reason is that temperature can dictate the speed at which stick insects grow. Increase the temperature and your stick insect can grow faster. Lower it and it is possible that your stick insect will slow down its rate of growth.

Nonetheless, this is species dependent. Each species will have different preferences when it comes to temperature and humidity. This is especially the case if you intend on keeping exotic stick insectsOpens in a new tab..

Last Word – What You Need to Know About Stick Insects and Adulthood 

The most important take-away from this guide is that the concept of adulthood is not the same for stick insects as it is for humans. Adulthood for a stick insect is the final phase of its life and you should not expect, for example, a female stick insect to live any more than six months from that stage. A male will only usually live for a month or so after reaching adulthood.

This makes it so important to track the shedding stages of your stick insect; it helps you know when it has reached its full size.

As you get to know your species, you will be able to spot exactly which shedding stage they have reached based on sight alone.


I am a content creator by profession but exotic animals are one of my great passions in life. Over the course of my adulthood, I have had the pleasure of looking after stick insects, terrapins, an Egyptian tortoise, giant African land snails, a crested gecko, a Chilean rose tarantula, a couple of curly-haired tarantulas, and a selection of millipedes, centipedes and worms!

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