I often get questions about how to raise caterpillars. One of my first jobs during college was raising caterpillars, which lead to similar jobs throughout the years. Why raise a caterpillar? Not only does successfully taking care of another living thing lead to insights into its biology and behavior, but also when a beautiful butterfly or moth emerges, it is an amazing experience.
A few weeks ago I wrote a post about white-lined sphinx moth caterpillars.
In the update I mentioned that I had placed a caterpillar in a terrarium with moist potting soil (about five inches deep). The caterpillar immediately disappeared, but I knew where it had gone. Large moth caterpillars, like white-lined sphinx moth caterpillars or tomato hornworms, dig into the soil before pupating. Their pupa looks like a dark reddish-brown cigar. Saturday I found the moth sitting on the cloth I had used to cover the terrarium. It had successfully emerged.
Here it is.
Because white-lined sphinx moths are big and active, they need a lot of nectar to keep them going. After taking a few pictures, I immediately let it go. Here’s a link with some amazing pictures of white-lined sphinx moths. This entire website is full of great information and photographs.
What do you need to raise caterpillars? It does depend on what kind, but here are some general guidelines.
1. Unless you are using a kit that supplies special food, you will need large quantities of fresh plants. And not just any plant, most caterpillars will only take one or a few kinds of plants as food. Once a tiny larva has started eating one kind of plant, they often will refuse to take anything else, even if other members of its species will. A good rule of thumb is only bring home caterpillars that you are absolutely sure you know what they eat, and you have lots of those plants available to feed them. Edit: What white-lined sphinx moth caterpillars eat.
2. Provide a clean, safe container covered with screen or cloth to allow for air circulation. It is best to keep the container outside in as natural conditions as possible. Insect life cycles are extremely sensitive to light and temperature. If you bring the critter inside where it is cool and dark, it may emerge days or even weeks after wild members of its kind and may miss critical windows of opportunity to perform necessary behaviors like mate or migrate.
3. Keep only one or a few in a container. Crowding insects into small containers greatly increases the chances for disease. Insects can get viruses, bacteria and fungi, which can make them sick, just like those things can make humans sick.
Scientists have suggested that monarch butterflies may migrate because of a parasitic infection. This parasite (a protozoan) causes the butterfly to be weak but not die. By going on long migrations, the sick individuals are left behind. When we handle monarchs, we risk spreading the disease even more. Let me know if you’d like more information about this.
4. Provide sticks for butterfly caterpillars to climb on when they are about to make their chrysalises. Moth caterpillars will need plenty of moist soil to dig into. Other caterpillars may like to have different substrates to pupate in, like cloth or egg cartons.
5. Insects are also sensitive to humidity, especially when they are molting. It can be tricky, but try to keep the humidity up without getting the container too moist. Too much humidity can cause things to get moldy.
I hope these guidelines doesn’t sound too negative. Having a lot of experience, I have a better idea of all the things that can go wrong and I wanted you to avoid the problems. And oh yes here’s one more: don’t leave the lid off the container once the caterpillars have pupated. My son did this, and we had cabbage-looper moths all over the house. (It was actually a hoot!)
One great way to raise caterpillars is to plant butterfly and moth plants in a butterfly garden. (Check out an earlier post on butterfly gardening.) Then the caterpillars do all the work themselves.
Also, don’t forget to take a look at some of the butterfly and caterpillars books for children.
And finally, my friend Debbie called again. Her passion vine plants now have gulf fritillary caterpillars on them (see last week’s post for details).
It is great that you are allowing your plant to be caterpillar food.
If you think it will have enough soil, it probably would be better off if you just slipped the smaller pot into another, larger pot after it pupated. That way it would be extra protected, but you wouldn’t need to transplant it. You could even add some insulation between the two pots to help protect it.
Sounds like a good place for it.
My white lined sphinx moth came out today after spending the winter in my garage! I just about gave up on it because I set it outside and then we got a blizzard in April, so I was afraid it had died. Then earlier this week I noticed the wings were showing through the chrysalis. (The dirt got moved away from it) I checked it this morning and it hadn’t come out, and didn’t get around to checking it again until after t-ball tonight. It’s wings were dry, but it didn’t look ready to fly yet. The mystery one that also spent the winter in my garage was moldy this spring when I brought it out, so I don’t think it made it.
Stefanie,
Thank you for reporting back. I’m so excited that your white-lined sphinx made it through the winter. Congratulations!
I found a white-lined sphinx caterpillar while chopping down a vine that was overgrown in my front yard. I think however that was it’s food and now I feel bad that I might have killed this little guys food supply. would it be wise for me to try to keep the caterpillar or should I toss him in a bush and hope for the best?
thanks!
White-lined sphinx caterpillars can eat a lot of different plants, so it will probably be just fine if you let it go.
Other kinds of caterpillars can be very picky and might need to be released near the same kind of plant they were found on.
I’m not entirely sure what type of Hawk Moth it was (leaning more towards Manduca sexta) but she ended up laying 35 eggs before I accidentally killed her (I was trying to get the eggs that were further up on the screen and accidentally crushed her with the window) and it has been two days so far. I have the eggs in a small, empty container with a lid on it. I’m worried that when they hatch I won’t have any dirt for them and I already know I’m going to have to spend money to buy the type of plants they like to eat. If you know anything on raising these types of caterpillars please help me. I really don’t want them to die and I feel as though I owe the moth I accidentally killed.
Paige,
Sorry to hear about the moth accident.I can understand you wanting to make amends.
Do you have any plants outside? You could place most of the eggs outside near plants that might be food plants, and hold only a few to take care of.
I recommend you take a look through the information at the Manduca project website. They have a lot of advice about rearing. http://insected.arizona.edu/manduca/default.html
ASU has some great ideas for experiments with rearing Manduca, too. http://askabiologist.asu.edu/manduca/enter-lab
Good luck!
Thank you so much! Yesterday all but three eggs have hatched and they’re all doing great! Thank you, thank you, thank you! Now I finally have a website that can actually help me and tells me how and when they’ll grow. I don’t know what I would of done without your help.
Thanks for the feedback, Paige. Wishing you continued success.
Thank you so much for this article. My 5 year old daughter caught a pair of Western Sphynx moths mating and the female laid eggs in her terrarium. About 30 of them hatched June 1 and were doing well until we fed them the wrong kind of leaves and all but one of them died. The surviving one had a noticeable change in color today (redish hue along its back) and quit eating and pooping, and was much more active all day than it has been up to this point, but we didn’t know that it needed dirt to pupate until we found this article. It started digging down as soon as we put dirt in the jar for it. How moist should the dirt be?
After finding a sphinx moth caterpillar on a wood vine on my front porch, I put it in a bug barn and kept a steady stream of vine leaves available. It pupated a couple days ago; as it’s only the middle of July, is it going to overwinter now, or will it emerge a moth yet this season? I think it’s a little early to begin over-wintering. I’m in South Dakota and it’s our hot, hot season.
Amber,
Isn’t it cool to see it dig down once it finds soil? Your soil should be about as moist as a wrung-out damp sponge. You definitely should not see standing water anywhere.
If you have it in a jar, be sure to give it a stick or pencil to climb up on once it emerges. The moths need to hang on something to dry their wings properly.
Lynn,
Chances are good that it your sphinx moth might come out this season. If not, don’t give up on it. Keep it moist and keep checking.
If you think of it, we’d love to hear what happens.
I had no idea I was supposed to provide the caterpillar soil to pupate in. It just laid on the leaves & started changing. (my husband thought it was dying). Should I put soil in the bug barn? The bug barns I have are left from my bug-crazy kids–they’re U-shaped mesh over a wood frame with a wooden handle on top and a round opening on one of the wooden ends that seals with a plastic lid–my husband built about six of these so each kid had two. I could put a small pan of semi-moist soil in for the pupae if you thought it would do any good. I don’t want it to dry out.
Lynn,
You know, you could just spritz the leaves once in awhile with water, too. You are probably more humid there than we are here in the desert of Arizona, so it might be okay without soil.
My 6 year old and I found a big white-lined sphynx caterpiller a few days ago and have it in a jar and been feeding it various plants and veggies. I just read that it needs dirt so we added some to his jar. My question is where should i store the jar as I’m assuming he will emerge in the spring? We live in Minneapolis MN so winters are VERY cold.
Karmen,
I would recommend a cool, protected area like a cellar or well-insulated garage. If it pupates, you might still keep an eye on it, because some people have had them emerge in the fall.
Sphinx moth!! Three weeks and three days after the caterpillar pupated, the moth emerged! I did put a dish with soil in the bug barn, and put the pupae in a hollow in the soil. I left it on my front porch (west facing), which is shaded by the vine where I found the caterpillar. I could tell “things” were happening yesterday, as the pupae turned a very dark, rich brown color and was very active (if you touched it gently with a twig, the pupae squirmed). Today after work I checked it, as I’ve done every day, and the moth started madly fluttering, trying to escape. We took a couple pictures and released it in a huge flower bed. It flew away, but I’m hoping it will be back to visit the flowers at dusk. Success!! So Karmen, you might very easily have a moth yet this year. I’m in South Dakota–hot in summer and COLD in winter, & mine emerged after less than a month. Thank you for your support, Roberta!
So Lynn did you move your caterpiller once and it pupated? I didn’t realize how big of a moth is will be once it emerges and it dug down into the soil before I mi ved it to a bigger jar :/ I dont want to disturb it if it will effect the process. Currently he is just in a quart canning jar. There is a stick in there but im assuming that isnt big enough?
I put the caterpillar in a “bug barn”, which has a wood floor & ends, covered in fine mesh wire, so it is open to the air. It pupated on top of the bed of leaves, and I gently moved it to a small dish of dirt, but didn’t bury it in the dirt–just hollowed out a spot so the pupae was swaddled with dirt, and kept the dirt misted. The barn sat on my screened porch, open to the elements & the temp changes from night to day, but in the shade. I wanted to create as natural an environment as possible for it. I didn’t have a stick in it, but it could hang from the fine mesh screen just fine, which is what it did. I think you could carefully move it to a bigger jar–or better yet go to a 2nd hand store and get an old aquarium & put screen over the top. the pupa will wiggle, so be very gentle!! Good luck, Karmen.
Thank you so much Lynn, for sharing your experiences. I agree with your advice, an old aquarium with a screen would give the moth enough room. If it can’t climb the sides, be sure to add a stick for it to hang from.
Awesome!
3 weeks and 1 day pupating under the soil and our moth finally emerged today! 🙂 I was a little concerned because it just layed there for about 5-6 hours but finally his wings started buzzing and he took off! What an amazing sight to see! Thank you for all your advice. I have never seen one of these moths before so to be able to watch and raise one during its life cycle was so cool!! -)
Karmen,
So glad to hear of your success. Yes, they do sit still as the wings develop.
Did you end up getting a bigger container?
I Just found a White-Lined Sphinx caterpillar on my front pouch tonight. I am wanting to keep him, but not sure what he was eating. Should I just put a variety of plants in there until I see what he eats? Also heard it may eat apples and or tomatoes. Thanks
Michael,
If you found it on the porch, it might already be in the wandering phase, searching for a place to pupate. You might want to put it into a container of damp soil and add some vegetation on top of the soil. It can’t hurt to try different things and keep a close watch. If it digs into the soil and pupates, you will want to take any food you gave it out promptly so it doesn’t get too moldy.
Good luck!
Hey, I found a white lined sphinx caterpillar and I want to take care of it. But I live in north east Kansas and I can’t find any plants that are listed on what they eat. All I have around my is grass and oak tree and a flaming bush. Do you know if there’s anything around here I can get it to eat.
I found a lunar moth caterpillar and put it in the soil it dug down on its own and I dug it up today October 6th it is a big black cocoon you touch it and it goes crazy it has been in there for 13 days now it was 51 degrees last night when should my caterpillar emerge your soul is also dry I don’t know if I should spritz it with water because the cocoon is so close to the top of the sandand what should I do it is in a decent sized vase but I am afraid when the butterfly emerges it will not have enough room to spread its wings
Sammy,
Sorry it took so long to get back to you. I have been away from my desk. Did you find something to feed it?
-Roberta
Mark,
Your concerns are valid ones, but first of all I should let you know that luna moths don’t pupate in the soil. They make a cocoon, usually in dried leaves or in shrubs. If the pupa is black, it might not be a white-lined sphinx either. So, it will be interesting to see what emerges.
I would spritz the soil with water if it feels dry. Since it isn’t clear what kind of moth it might be, you might consider trying to move it to a bigger container, too.
I didn’t need to, he ended up burrowing that night. I’ve been keeping him outside but it’s really bad and rainy outside so I bring him in so his little habitat doesn’t fill with water! I can’t wait to see him come out in the spring!
I have a couple of Giant Leopard caterpillars in a Costco size plastic cookie jug with soil and a nice bed of leaves they seemed to enjoy covering the bottom. I had two, one kinda large and another smaller and they seemed to be doing fine. Then all of a sudden now I can’t find either of them. I don’t want to disturb the dirt now that I know they could be in it. I just found three more HUGE caterpillars of the same kind and realized the original two were actually kinda small so now I’m wondering if they could even have been ready to transform since they were littler or if they just dug themselves a hole to die in. These are the coolest caterpillars and I would hate to be doing nothing more than trapping them and letting them die. I have the biggest of the ones I found in another container with the same soil and lettuce since I’ve found they like that as well. I’m not exactly sure what to do with the jug now… how long do I wait before cleaning out the jug? Also, as soon as I put the biggest caterpillar in his new home he started circling the perimeter of the container over and over again…. is this normal?
Chelsea,
You have a lot going on! First, the circling is absolutely normal. When the caterpillars are ready to pupate, they wander away from the food. If they don’t have room, they don’t wander in a straight direction, but circle around instead.
About the size, sometimes moths and butterflies of one kind can be different sizes. It might be the males are smaller than the females, or it might be the food they were eating wasn’t the best and they are a little stunted. If they went into the soil, it is likely they were ready to pupate.
If you get a chance, let us know what happens.
Chelsea,
Here’s a blog post about a giant leopard that pupated in a cardboard box. http://mothhunt.blogspot.com/2009/07/giant-leopard-moth-caterpillar-to-pupa.html You might want to try giving them a cardboard egg carton. Silkworms really like to make their cocoons in those.
Thank you! I didn’t know they went under the soil to pupate so I only have like maybe 2 inches of soil in there. Should I add more on top? I love these moths so I keep trying to save them because they fall out of a tree onto my yard and then they get lost I feel. I found one dead in the middle of the yard because we have frost every morning now and the poor little guy couldn’t get to a safe place in time. I find them quite often in the grass and I’m scared my father is going to kill them when he cuts the grass since he was still doing that up to a week ago. I will definitely keep you posted.
How do I utilize the egg carton?
Do I fill it with soil and place it on top of the soil I already have in the container?
Again, thank you so much. I hope I didn’t make things any worse for these poor little fellas…
Chelsea,
If they are going into the soil, then you probably should would leave it alone.
I suggested the egg carton if they didn’t seem to be going into the soil, because some kinds of caterpillars like to make their cocoons in leaves or under the bark of logs and they might have used an egg carton instead. But since these are going into the soil, then that must be what they prefer.
Good thing you noticed them, although some of them are probably going to be okay.
Roberta,
I’m so glad to have found your blog with active comments! I don’t have a sphinx moth caterpillar, but I have been raising another type (I don’t know what it is). Started out very green and after a few days of eating and eating, it stopped eating and got paler in color. Then it ate again for a day or so. After that, it stopped eating again and suddenly turned dark red/brown overnight. I had a twig in the glass jar the whole time so it wasn’t pupating there. I added soil and it circled the perimeter like crazy as another commenter described. Looked like it wanted to leave, then finally it dug under the soil and was gone for a whole day. I slowly dug into the soil just now to find it, hoping that it spun it’s cocoon, but I found it just cuddled up in the soil. It did not like that I found it jerked around, I felt bad about that. How long does it take for caterpillars to just lie around like this before they pupate? Is there something wrong with mine?
Edit: Near the bottom of my paragraph, I meant to say: It did not like that I found it so* it jerked around.
Pamela,
Pupating is a long process. First the caterpillar enters the “prepupa” stage. The prepupa might look stiff and odd. That is okay. It might take it a couple of days to pupate, depending on the temperature and if the conditions are optimal. A moth pupa will be a reddiish-brown color and may darken with age. Most do not really form a cocoon underground, but merely a chamber in the soil.
Hope this helps.
my Moth hatched this morning.now I don’t know what to do as it is winter time. I didn’t realize it was going to hatch and it’s 19 degrees outside.
Tiffany,
Oh dear, that is one of the hazards of raising moths indoors. If you’d like to try to feed it, mix some sugar and water together. Use 1 part sugar to 4 parts water, which is the same as hummingbird food (hummingbirds also drink nectar). Dampen a clean sponge or clump of paper toweling and offer it to the moth in its container. It may take the moth quite a while to pump up and dry its wings, so don’t be alarmed if it doesn’t feed until tomorrow.
I’m not sure what else you can do.
I recently found a white lined sphinx moth in Santa Ana and I hadn’t seen one in that area before so I caught it , after a night I looked in the container and there’s probably about 100 little green eggs scattered across the container I want to raise them but I’m not too sure about what temperatures the eggs need to be at ,what to feed them and what kind of a habitat they prefer . I’m new at the whole moth thing so some advice would be splendid
Brooklyn,
Thank you for your interest in moths!
Well, because the moth laid eggs so quickly, I would say the eggs are probably fertile, which is good.
As for temperature, room temperature or slightly above will work just fine, although the moths you rear may not be on the same cycle as those outdoors if you are thinking of releasing them.
You probably don’t want to feed 100 hungry little mouths, so I would release at least half the hatchlings outdoors on a host plant. White-lined sphinx caterpillars will eat quite a few different plants, including purslane, spurge, primrose and even grape. I have some information about what they eat here: http://blog.growingwithscience.com/2008/10/what-white-lined-sphinx-caterpillars-eat/ I would try offering them some of your local weeds and then keep feeding them the ones they prefer.
A plastic container or terrarium would be best because you will want to be able to wash it and keep it clean. To clean their cage, put the growing caterpillars in a holding bin (a paintbrush helps move the smallest hatchlings), remove the wilted plants, clean the container and the put in fresh food. That should be done each day, if possible. Once the caterpillars start their wandering phase (see post) you will want to offer them about 2-3 inches of soil to pupate in.
Good luck, and feel free to return if you have questions. Anyone else have suggestions for things that worked for you?
Was looking up how to raise butterflies and this blog came up.
Have to say it’s been very helpful reading the comments, I do have a question…I’m ordering some Cabbage white butterfly eggs this week and found some information on what they eat as well as what can be used as a substitute when not using seedlings. Would kale work?
I have some that is store bought and is the type that’s already been washed and can be used right out of the bag as a salad. I plan to switch to broccoli and Brussel sprouts when the caterpillars get older.
I’m nervous as this is my first time raising caterpillars from eggs, I did raise cabbage whites years ago that I found on a tomato plant and they eventually became butterflies.
Any help would be greatly appreciated.
Thank you!
EC,
Kale would be fine to feed cabbage whites. Whenever you are feeding insects, use organic produce if possible to avoid accidental exposure to pesticides.
Also, just FYI, some caterpillars get used to eating one kind of plant and will not switch, even if other members of the species will eat that plant. Broccoli and Brussel sprouts are botanically the same species, Brassica oleracea, so the caterpillars should be okay. If they do seem to have reluctance to eat the new food, try switching back.
Thanks, I did use organic kale.
The cabbage white eggs I ordered came in the mail yesterday, as of today, I have three caterpillars that are just a few hours old, walking around the jar and eating the kale. I’ll be waiting to see if any more eggs hatch as well as taking photos and videos to document their growth.
Thank you for your help!
Fabulous! Good luck with your project.
Thanks.
I do have one other question, if a species occurs naturally in a certain state, is it safe to release the ones you raised if they’re the same butterfly?
EC,
That is an excellent question. Although there aren’t many rules against it, there are good reasons not to release human-raised animals back to nature. For example, caterpillars raised together in artificial conditions are more likely to spread diseases or parasites to each other, and then pass the diseases or parasites to naturally-occurring insects when released. Even if the insect is considered to be a pest, those diseases or parasites might also impact beneficial insects, too, for example honey bees or monarch butterflies. Some examples here: http://monarchparasites.uga.edu/parasites_in_monarchs/
Oh, I see…thanks for the info, most moths and butterflies I’ve released before were wild caught as caterpillars. I know some websites offer butterflies to release during special occasions, though I don’t know how long they last in the wild after that.
I saw a 4 inch fat caterpillar (green with a brown purple back and a bumpy horn on it’s rear end) on my porch. Should I try to raise it and if so how?