No. 38 Bring up a butterfly

Red admiral butterfly a migrant species from Europe, nectaring on a flowerhead, on the east side of Lundy Island, Devon — A red admiral butterfly rests on a flower | © National Trust Images/Nick Upton

Watching a wriggly caterpillar turn into a magnificent butterfly is fun. Discover our top tips for giving a caterpillar a good home and match pictures of caterpillars up with their butterflies. Find out the best way to release a butterfly once the transformation has taken place.

What you'll need to raise a butterfly

The first thing you'll need to find is a place for your caterpillar to feel at home. A small tank, netted cage or plastic tub would all work well. It’s great if you can see through the sides, so you don’t miss any of the action.

Use fine netted mesh or a plastic lid with very small, smooth holes to cover your container. This will give your caterpillar lots of fresh air, while making sure it doesn’t escape.

You will also need:

A few pencil-sized twigs for climbing and leaves for eating.
Kitchen roll to line the bottom of your tub.
Water spray to make sure your little buddy doesn’t dry out.
And, of course, a caterpillar!

Choose your new pet

You’ve made the perfect place for your caterpillar. Now you need to find one! Going on a caterpillar hunt is all part of the fun – why not invite your family or friends to join you?

Search your garden or nearby green spaces for caterpillars or eggs. The best places to look are under leaves with fresh bite marks, around vegetable patches, or in hedges.

Caterpillars love to eat nettles, so keep a lookout for these too – but take care not to get stung. It’s always best to check with an adult before you go seeking.

A peacock caterpillar and butterfly

Move the slider to see it transform

Slider with before and after images

A peacock caterpillar at Cannock Chase, Staffordshire — A peacock caterpillar and butterfly | © National Trust Images/Rob Coleman

Hold on to the leaves

Keep hold of the leaves you found your caterpillar on. These are probably its favourite food and will be useful when it comes to dinner time.

Beware of hairy caterpillars

Be careful if you discover hairy caterpillars. Some hairy caterpillars can cause a rash and make you feel unwell if you touch them. Although most will cause no harm at all, it’s best to steer clear of them anyway.

Get to know your new friend

Some caterpillars are well-camouflaged and hard to find, while others are brightly coloured and have patterns to scare off predators. What will you discover?

Once you’ve found your perfect caterpillar friend, you’ll need to do a bit of research to find out more about it. What is it going to turn into? How long is its life cycle from caterpillar to butterfly or moth? What does it like to eat?

Look in books, search the internet, or ask an expert if you know one.

A swallowtail caterpillar and butterfly

Slider with before and after images

A swallowtail caterpillar in Norfolk Broads, Norfolk — A swallowtail caterpillar and butterfly | © National Trust Images/Rob Coleman

Swallowtail butterfly in flight, Norfolk Broads, Norfolk

Looking after your caterpillar

Caterpillars love to munch on small cuttings of fresh leaves every day and they might like some bark and pencil-sized twigs to crawl over and hang from.

You’ll also need to clean them out regularly – old leaves and caterpillar poo can go mouldy, which might make your caterpillar sick.

You can bring up your butterfly indoors, but keep its home out of direct sunlight so it doesn't get too hot. Kitchen roll is great for keeping your container dry, clean and free from damp too.

Once your caterpillar has become a pupa or chrysalis, it’s time to step back, watch and wait. Carefully remove any leftover food and spray a tiny bit of water every few days so it doesn't dry out, making sure not to disturb your sleeping beauty.

A friend for life?

It can take as little as four weeks for your caterpillar to turn into a butterfly, or as long as a whole year. It depends on the season and the type of caterpillar you have chosen. It will eat lots and then become a pupa or chrysalis, before emerging as a butterfly or moth when it is ready.

You could keep a diary with notes, drawings, photos and even videos of the different stages of your butterfly’s lifecycle. What colours, patterns and textures do you notice in the different stages?

Spreading its wings

The moment has finally arrived – your fluttery friend has emerged! If you're lucky, you may see it slowly unfurl its wings as it wakes up from its sleep. What does it look like? Was it what you expected?

More than 2,000 species of moth have been found in the UK, so there's a good chance your caterpillar may turn into a moth rather than a butterfly. Either way, your winged pal will now be ready to explore the outdoors, find a mate and begin the cycle all over again.

Time to let go

Watch as your butterfly stretches its wings and flies away. See if you can follow it as it flutters from flower to flower. Where does it choose to land first? Does it look different in the wild?

Before you gently release your butterfly or moth into a safe space in the wild, make sure you take a photo or drawing for your diary, so you always have the memory.