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Do You Need To Give Monarch Caterpillars Water?

Caterpillars are a wonderful pet and very simple to care for overall, but if you are keeping monarch caterpillars for the first time, you may be wondering do monarch caterpillars need water or should you keep them in a dry environment? Many insects are harmed by having too much water, so it’s important to know what you are doing if you are going to successfully raise monarch caterpillars. You don’t want to drown them, but you also don’t want them to dry out completely.

Monarch butterflies are stunning insects, and many people choose to take and raise some of their eggs, either for their own enjoyment or for the sake of teaching children about the transformation process that a caterpillar goes through. Whichever you are doing, you need to know how to care for the caterpillars properly to ensure that they reach the point where they can turn into chrysalises and then into butterflies. This involves understanding the things that they need and providing these to the best of your ability.

If you don’t meet a caterpillar’s needs, it will quickly die, as these are quite delicate creatures due to their small size. They don’t have the ability to withstand long periods without food and water, and if you want to keep them alive, you’ll need to provide both of these things in sufficient quantities.

Do You Need To Give Monarch Caterpillars Water?

Like almost all creatures, monarch caterpillars do need to drink, and they will usually get sufficient water from the plants they consume – but these won’t always provide enough. If you don’t keep an eye on the hydration levels, your caterpillars will shrivel up and die surprisingly quickly, especially if they are kept in a warm environment. Although the plants may provide some water, cut plants quickly lose water themselves, so you need to be aware of what is going on.

You should be cutting suitable plants for your caterpillars to eat, and these often will provide quite a bit of moisture when they are freshly cut. If you are cutting plants every day or every two days, you should find that you don’t have to give the caterpillars additional water, because they will get plenty of water from the plant’s sap when they eat its leaves.

However, if you only cut the leaves every few days and they are allowed to dry out a little in between feedings, you may have to also give the caterpillars water to keep them hydrated. It is best to make sure that some water is available if the leaves are looking dry, so keep an eye on them, particularly during hot weather.

Should You Supply Monarch Caterpillars With Water?

If the leaves of the plants are dry, you might need to supply monarch caterpillars with water, yes. In the wild, the caterpillars would simply drink dew off the plants when thirsty, or get all the water they need from the sap of the plants. However, in captivity, caterpillars might need a separate source of water, although you should only supply this if the leaves of the plants are dry and you can’t change them.

It can be challenging to provide water separately, because caterpillars are very vulnerable to drowning, and could easily kill themselves if you put a bowl of water into their enclosure. They might fall into it and find themselves unable to crawl out, in which case they will certainly drown and sink to the bottom – something that you will certainly want to avoid, especially if you are teaching young children how to care for caterpillars.

The water supply must therefore be safe for caterpillars to get water from, with no risk of them accidentally drowning themselves, and no risk of the water drying up before you have a chance to replenish it. Again, hot weather is the time at which this is particularly problematic, because the water supply will dry up faster, and the caterpillars will be in greater need of a drink. You must supply water, but doing so safely can be a challenge, and we’ll cover this in the next section so you know how to approach this.

What Is The Best Way To Provide Monarch Caterpillars With Water?

The best way to provide monarch caterpillars with water is to ensure that they always have fresh leaves to eat, and to gently spritz these leaves with a little moisture if necessary. The leaves will spread the moisture out, removing the risk of the caterpillar drowning in it, but ensuring they still have ready access to everything they could need. Caterpillars are so small that just a few drops of water sprinkled across the plant they are eating should be sufficient, and they can avoid these if they do not need a drink when they encounter them.

You can use a plant mister to create a fine spray, or you can simply flick some water onto the leaves using your fingers or a clean toothbrush or paintbrush. You could run the leaves under a tap instead, but you will need to shake them quite dry before putting them back in the enclosure, because excessively damp conditions could lead to mold, which might kill off the caterpillars.

If you have very young caterpillars or you are still looking after eggs, make sure you give them a very light misting with a plant sprayer each morning, but allow them to dry out a bit throughout the day to reduce the risk of fungal infections. Older caterpillars should get all the moisture that they need from the plants they are eating, unless the leaves have dried out too much.


So, do monarch caterpillars need water? Yes, they do, but they will get most of this from the plants that they eat, and you should only supplement the water supply with extra if the leaves have dried out a lot and you haven’t got time to change them yet. In other circumstances, the caterpillars should get everything they need from the plants they eat.