Many, many years ago, the people of China in the Shang Dynasty discovered that raising caterpillars is easy to do. All that was needed were clean, secure shelters to house them in, a little water, fresh leaves from their favorite food plant (in this case, mulberry leaves), and of course, a little time and patience. When the silkworm caterpillars (Lepidoptera) were ready, they would transform into small golden lumps, otherwise known as cocoons. These could be spun into a versatile fabric called silk, which was highly valued by anyone that saw and touched it. Everyone seemed to want it, wars were fought over it, and many caterpillars were smuggled out of China only to die along the way to Europe.
Caterpillars are our first domesticated insects. They were raised by people over 4,000 years ago, long before honeybees were raised!
A few thousand years later, silk is still well loved and produced in enormous quantities. Billions of caterpillars are raised each year for the silk industry alone! Besides silk, other caterpillars are raised for conservation efforts, education and even for the simple joy of fostering a potential monarch butterfly or cecropia moth. Although you might not want to start your own silk empire, raising a caterpillar is lots of fun, very educational and easy to do. It’s not expensive, takes up little space, and smells a lot better than most other pets. The hardest part of raising a caterpillar is to set the adult moth or butterfly free and say goodbye. Don’t be sad! This act can help the environment in many different ways, and is also a great wish-making opportunity. GOOD LUCK!
Before you start … here are a few important things to remember!
LEARN about your subject. Visit your local library and borrow all the books available on butterflies and moths. Or better yet, go to your favorite bookstore and buy a good field-study guide. Learning about butterflies and moths before you try to raise one will help you find, identify, and care for your specimen.
BE CAREFUL! Some caterpillars are poisonous, some are prickly and others produce terrible smells when disturbed! When looking for a specimen, bring along your field-study guide to help you identify the caterpillars you find.
CONSIDER: It is always best if you can find everything you need in your own backyard. Although it seems fun and adventurous to go collecting in the wild, it’s also unpredictable. There’s poison ivy and stinging-nettle to consider, not to mention biting insects, wary creatures, bad weather and angry grounds-keepers who will not appreciate your ‘borrowing’ food-plants or collecting specimens that are already at home where they are. If curiosity overcomes you and you must go into the wilderness, please leave your equipment behind and bring your camera and take pictures instead.
FINDING YOUR SPECIMEN:
Moths and butterflies spend their lives in four different stages. First as an egg, then as a caterpillar, then becoming a chrysalis or cocoon and lastly, emerging as a butterfly or moth. It will probably be easier for you to start by looking for a caterpillar rather than for eggs or pupae. Caterpillars are more visible and will lead you right to themselves by leaving a trail of stripped branches and half eaten leaves. Caterpillars are also much easier to identify than eggs or pupae, and by collecting a caterpillar instead, you can avoid raising an undesirable bug by accident.
Speaking of undesirable bugs … there are a few caterpillars that aren’t worth raising, such as Gypsy moths and Tent caterpillars. Both have special hairs that can irritate your skin and both are destructive pests.
Here are a few caterpillars that are commonly attracted to backyard gardens:
- Tomato Hornworm. The larva of the tomato horn moth, a large mostly green caterpillar with a horn near its tail end. Look for the tomato hornworm on tomatoes, eggplants, peppers or potatoes. NOTE: If you're going to raise a tomato hornworm, be sure to put a two to three inch layer of this soil mixture in the bottom of the tank: 1 part sand, 1 part sifted topsoil and 2 parts well ground peatmoss. These caterpillars like to pupate underground.
- Cabbage White Caterpillar. The larva of the cabbage white butterfly is a small green caterpillar with no protrusions and minimal markings. Look for the cabbage white caterpillar on cabbage, broccoli, brussel sprouts or kale.
- Black Swallowtail or Parsley Worm. The larva of the black swallowtail butterfly is a green, black and yellow striped caterpillar that might surprise you with its osmeterium! (a 'Y' shaped horn that appears when the caterpillar is disturbed – it may squirt foul smelling liquid!), don’t be discouraged; this caterpillar will turn into a stunning swallowtail butterfly! Look for it on parsley, carrots, Queen Anne’s lace fennel or dill.
- Monarch Caterpillar. The larva of the familiar and beloved monarch butterfly is a large black, yellow and white striped caterpillar with a pair of black horns at each end. Look for the monarch on milkweed.
WHAT YOU’LL NEED:
- A temporary home for your caterpillar in a dry, shady location. A glass or plastic aquarium with a lid works best, as long as there’s enough room for delicate wings to spread out and dry. Try to set it up to look as natural as possible with plenty of twigs and leaf litter.
- Food! Caterpillars are eating machines, and need to eat constantly. Provide your caterpillar with plenty of its favorite foodplant, well rinsed and preferably still attached to the twig. Keep the leaves fresh by putting them in a glass of water. Accept no substitutes! Caterpillars are very specific about what they like to eat, and won’t eat anything else. Also beware of pesticides; remember that your caterpillar is an insect, and pesticides will kill it. Rinse all food-plants well or use alternative pest control methods.
By picking caterpillars off of your garden plants, not only do you get a specimen to observe, you are also organically controlling a potential pest problem!
When you’ve found a caterpillar, remove it from the plant it’s eating with a small paintbrush or your fingers. Do this very gently; caterpillars are merely squishy tubes! You can also clip off the branch that’s hosting the caterpillar, specimen and all. If you do this, check the branch thoroughly in case it’s hosting other things you might not want to raise. Quickly transport your specimen to your habitat. Watch, learn and be amazed!
WHAT TO EXPECT?
Each different Lepidoptera species goes through its cycle at its own pace. Generally, they spend four days to one week as an egg, two to five weeks as a caterpillar or larva, five days to one month as chrysalis, cocoon or pupa and one week to eleven months as an adult butterfly or moth. Here are a few things to look forward to along the way:
Your caterpillar will grow! In the larval stage a Lepidoptera will grow quite a bit, and at a very fast rate. As it grows, its skin will split, revealing a larger caterpillar with possibly bolder, more defined markings. Each time this happens, your caterpillar has reached another instar (larval growth stage), and depending on the species, can go through as many as nine instars. After shedding its skin, the caterpillar will probably eat it.
Your caterpillar looks like it’s turning inside out! If your caterpillar is hanging upside-down while moving around strangely, chances are it’s trying to pupate. (Transform into a chrysalis or cocoon). Within 48 hours, it won’t look like a caterpillar at all. At this point, don’t touch or disturb it, but do continue to mist with rainwater daily. If your caterpillar is a potential moth, it will hide itself under leaves or pupate in the earth. Caution – over-misting can create a soggy atmosphere and drown your caterpillar.
Your chrysalis is splitting! When the butterfly inside is ready, it should really pop out of its chrysalis. It won’t look like a butterfly at first; its wings will be shriveled and wet. The new butterfly will put all of its energy into pumping its wings up and zipping its proboscis (tongue) together. This will take an hour or so. DO NOT try to help it! If all goes well, it should be fine on its own. If you’ve raised a moth, it will blast its way out of its cocoon using a silk-dissolving liquid. If it’s a sphinx moth, it will come out of its holes as an adult!
WHAT IS THAT?
Frass: Weird, brownish, greenish or grayish blobs; scattered throughout your habitat. This is your caterpillar simply responding to the call of nature, using its temporary home as a toilet. It’s completely harmless, but if there’s a build-up, it could go moldy or attract pests. The bigger the caterpillar, the bigger the frass!
If you’re raising cecropia caterpillar, those lumps can be as big as raspberries!
Maconium: You may notice it after your butterfly emerges from its chrysalis. It’s that liquid stuff that sometimes drips from the empty shell. In some species, it looks remarkably like blood but it is not. It’s leftover colour pigment from the making of the wings.
Once your caterpillar has successfully graduated from pupa to adult, it’s time to give it back to nature so that it can produce the next generation of butterflies and moths. Wait 24 hours after it emerges to ensure that its wings are fully formed and stable. If you can, try to release it where you found it originally. There may be others of its kind nearby. Remember not to handle the butterfly or moth by the wings, as you may rub off its scales and inhibit its flying ability. Let it crawl onto your finger or leave its habitat on its own. A moth will probably be happier if released at twilight, as they are generally nocturnal. As you release your specimen, make a wish! Impressed by your experience? Try planting a butterfly garden next!
PAINTED LADY BUTTERFLIES
Painted ladies are usually available in observation cups with lids. Most are sold as chrysalides, but sometimes they are available in the caterpillar stage. As caterpillars they need to stay in their covered homes and placed in a warm shady location. The caterpillar will continue to consume the food mix it was supplied with until it turns into a chrysalides. The Chrysalides should form hanging from the lid of its container. At this point remove the lid and pin the lid up in a warm bright location. (You may also be able to gently peel the silk off the lid it uses to hold itself on with, and pin the silk of the chrysalides up.) The butterfly will emerge and complete it’s metamorphous cycle in two to nine days. During this time as a chrysalides, gently mist it with warm tepid or bottled water one to three times a day depending how dry the air is around it. (Do not mist too late in the day if the nights will be cool.) Once your butterfly emerges it will want to spend some time allowing it’s wings to dry and form, preferably in a sunny location. When the butterfly is ready to fly, take it to a location out doors where there will be lots of flowers for it to choose from to feed off of. One should not touch a butterflies wings, allow it to step onto a stick or your finger, so that you can send it off to live it’s life as a butterfly.