Raising Monarch caterpillars

I can’t remember when I started raising Monarch caterpillars. I’m thinking maybe five years ago, and I’m no expert, but I’ve learned a few things.

First, raising Monarch caterpillars from egg to butterfly is a huge commitment of time, energy and milkweed.

Second, If you want to save the Monarch butterfly, plant milkweed. And, don’t just plant one plant in one area. Plant at least three or four plants in several areas throughout your landscape.

Learn about the different types of milkweed available in your area, including natives. Plant natives, but also, if you live in Oklahoma or further north, plant some Asclepias curassavica, tropical milkweed, too. Further south where tropical milkweed overwinters, you’ll need to cut it back to keep the Ophryocystis elektroscirrha (OE) infestation down. If you live further south, here’s more information about tropical milkweed. I’m not wading into the tropical milkweed controversy because I live in Oklahoma where tropical milkweed simply dies at the first freeze. I’ve also grown A. incarnata, swamp milkweed, and A. tuberosa, butterfly weed. Of the three types of milkweed I’ve grown, Monarchs seem to like butterfly weed the least. In order to get them to feed upon it, it’s good to cut it back several times in a season for new growth. Otherwise, the leaves are tough. However, it is a wonderful pollinator plant, and I have it all over the garden.

One more thing about milkweed, if you don’t grow it from seed, you must make sure the nursery you buy it from has not sprayed it with anything, including organic pesticides. Organic or inorganic pesticides will kill your caterpillars, and sometimes, you can ask all the right questions and still get accidentally-sprayed milkweed. It happened to me last year. The safest thing to do is to grow your own from seed, and never spray pesticides in your own garden.

Monarch caterpillar condo. Raising Monarch caterpillars
Monarch caterpillar condo. I don’t poke holes in my lids because I take off the lids several times each day to check on the caterpillars. That’s enough oxygen. Other people do poke holes. It’s up to you.

There are many things which can befall Monarchs, but I don’t want to discourage you. You win some. You lose some. In the wild, it’s estimated that the Monarch caterpillar survival rate is less 10% according to the butterfly experts at Journey North. If you raise Monarchs and have enough milkweed, the survival rate can go up to 85 or 90%, so occasional failures, while sad, are still the minority.

Monarch egg on milkweed leaf. This is very enlarged so you can see it easier, but they are about the size of a pinprick.
Monarch egg on milkweed leaf. This is very enlarged so you can see it easier, but they are about the size of a pinprick. I don’t have a macro lens, or I could get even more detail.

For the best survival rate, bring in only eggs and first instar-sized caterpillars. Some people will tell you to only bring in eggs, but I’ve had good luck with 1st and 2nd instars. Now, I should probably always follow my own advice, but occasionally, I go ahead and bring in a larger caterpillar. It’s hard to leave them out there in the wild. That makes me too much of a softie, and I lose some to tachnid fly, but it’s worth taking the chance as far as I am concerned. However, if you want the best success stick to the official party line: only eggs and 1st instars.

I start my eggs and first instars out in small plastic containers like these Sure Fresh Mini Storage Containers, 10-ct. Packs – Square. I use a plain paper towel and place the pieces of leaves with the eggs on them in the containers. I then wait for the small caterpillar to emerge. It usually takes two to three days. Once the tiny caterpillars emerge, I put a fresh leaf beneath them. You can get Water Pick florist tubes to keep leaves fresh. I bought some last week. Those tiny cats don’t eat much, and a leaf will last awhile in a florist tube.

Probably 3rd instar Monarch caterpillar in one of the plastic bins.
Probably 3rd instar Monarch caterpillar in one of the plastic bins. Nearly time to move them to larger quarters so they don’t have to crawl through their frass (poop.)

I change out the paper towel once a day, and sometimes twice when cats get larger. They need a clean place to eat, and the photo, above, shows how quickly frass can build up.

Once they get to 3rd instar or 4th, I put them on milkweed that is pushed down into a cup. I like soda cups because I can push the stems into the straw slots, and there isn’t danger of a curious cat drowning itself. I’ve never had that happen, but there’s always a first time. I watch milkweed consumption closely making sure I don’t run out of fresh leaves. The caterpillars are very hungry as they grow, and I don’t want them eating each other. Yes, that can happen. Gross, I know.

Monarch caterpillars 4th and 5th instars.
Monarch caterpillars 4th and 5th instars. I have caterpillars in all of the five stages right now. Nearly all were raised from eggs. Here, I used a bottle with a small neck. I needed a lot of milkweed this morning.

Then, I wait for the 5th instars to make their chrysalides. I place the cats in butterfly habitats like Insect and Butterfly Habitat – 24 Inches Tall and this shorter one, Miraclekoo Insect and Butterfly Habitat Terrarium Pop-up (12 x 12 x 12),  but I’ve seen people use other types of enclosures too. I try to keep all of my instar sizes separate so that I don’t have chrysalides and enclosing butterflies over still-eating caterpillars. That’s a no-no. There are lots of ways to do this, and I suggest, if you’re serious about raising Monarch caterpillars, you join one of the several groups on Facebook. I’m grateful for all of these Facebook groups because the members are so supportive and helpful. If the Monarch ever returns with the numbers and vigor it once had, these groups helped make that possible.

I wash the cages and bleach them with a weakened bleach solution at the end of the season. Then, I put them away until the Monarchs and other butterflies return. I’ve only raised Monarch and Swallowtails so far.

The Beautiful Monarch is the largest group I know of. They give good, consistent info about the general raising and enjoyment of Monarchs.
Raising Monarch Butterflies is another large group that I’ve learned so much from.

For more Oklahoma-targeted information, I’m a member of these two groups:

Oklahoma Friends of Monarchs and
Monarch Initiative of Tulsa

Also, I want to once again recommend Kylee Baumle’s book, The Monarch: Saving Our Most-Loved Butterfly. It’s a good resource and has beautiful pictures too. Below is a photo of one group of caterpillars that are almost ready to pupate. The sound quality isn’t that great, but I was just doing it off the cuff.

To learn even more about Monarchs and the rush to save them, check out Monarch Watch. To learn more about migration patterns and such, try Journey North, a website that logs information from watchers throughout the U.S. They follow and show on maps the great migration now happening. On Thursday, for my birthday, I’m attending the Oklahoma Native Plant Society’s meeting where Matt Fullerton with the Oklahoma Department of Wildlife Conservation (ODWC) will present information about the Oklahoma Monarch and Pollinator Collaborative. Did you know I-35 in Oklahoma is a major pollinator highway? We’re right at the center of Monarch migration, and I can’t wait to hear how Oklahoma is going to help save more butterflies. I think it’s exciting stuff. I hope you do too.

The meeting is on September 7, 2017, at 7:00 p.m. (6:30 for snacks and chatting) at 400 North Portland Ave, OSU-OKC campus, Room 196. Hope to see you there.

This post does contain Amazon affiliate links to help support the cost of my blog. I’ve bought all of these items so I can vouch that they work. Thanks for reading everyone.

23 Replies to “Raising Monarch caterpillars”

  1. I found this post fascinating, Dee. I admire you so much for committing to such an important project. I have swamp milkweed and butterfly weed but no cats this year — although I’ve seen quite a few monarch butterflies. I don’t use pesticides — organic or otherwise — but the farmer who plants our fields does and I’m wondering if there is drift.
    I am so glad you liked the TV show of my garden. I miss you, too. Chicago next year? P. x

    1. Hi Pam, it could be drift, but it could also just be predators. I go outside right after the Monarch females come through, and I’ll find eggs. If I wait a day or two, I’ll see little holes in the leaves and no caterpillars. I think the spiders, ladybugs, etc., get them. Poor little Monarchs.

  2. Great advice! I had to laugh at your counter, though. It looks like my kitchen table. Full of caterpillar houses and to make matters worse, my dining room table is covered with seeds I’ve collected! Glad I have a patient husband!

    1. Me too. Haha. I’m lucky Bill is as concerned about their welfare as I. I’m also lucky he loves gardening, not the actual doing it, but the results.

  3. Great info. I might try it next year if I can lure some Monarchs to my garden. I have swamp milkweed and this year add some butterfly weed. Hoping to get a nice stand of it going for next year.

  4. The tone of this post was perfect–encouraging and realistic. Believe it or not, our set-ups are nearly identical. I find that the commitment is pretty easy until they get to the 5th instar stage, and then the Milkweed consumption and the clean-up can be a little overwhelming…until they pupate, and then it’s easy for two more weeks. Sometimes decisions about when to release them can be challenging, too, especially if there are storms in the forecast or the temperatures suddenly plunge, like they are here in the north for a few days. Great post, Dee!

    1. Beth, those are all good points. I have about 16 in 5th instar stage, and I was afraid I wasn’t going to get them full before they made their Js. I finally put the fatties in my darkened dining, and all but two have made their Js. The other two are on their way. I think raising Monarchs is intuitive much like gardening. Deciding what to do when, you know?

  5. Thank you for sharing this information especially the information on the milkweed. I would have only planted one type. This is so fascinating.

    1. Hi Peggy, thanks so much for stopping by. Yes, it’s good to have several types of milkweed in several places. That way, the Monarchs won’t miss your patch. 😀

    1. Hi Sally, well, for the last few years, it’s been mostly a miss. I’ve hardly seen a single butterfly. 2015 was the worst in a long time. However, the last couple of years, I’ve gradually seen increasing numbers. I believe this is because of good weather in the central U.S., efforts at planting more milkweed, and people who care enough to plant milkweed and/or raise Monarch caterpillars indoors. I’m seeing an effect.

    1. Hi Annie, I’ve gotten seed from friends off of boards and by collecting my own. I did buy three tropical milkweed plants this spring from a trusted nursery owner. However, I don’t suggest that because anyone can have a spray accident. One of the best ways to find milkweed is the Xerces Society’s page: https://xerces.org/milkweed-seed-finder/. Be sure to look at the directions for your milkweed. Much of it needs a cold period for germination.

  6. I’ve toyed with the idea of raising them before (as recently as last month when I found some eggs and tiny caterpillars). I worry about getting enough milkweed to feed everyone. I don’t think I have enough in my garden. How much does a single caterpillar need to get to the point it forms a chrysalis?

    1. Hi Rebecca, good question. I don’t really have an answer though. I have about nine plants, and I’ve raised a lot of caterpillars so far. If the milkweed has time to regrow, you’re ok. It’s when everyone becomes a 5th instar at one time that things get a little iffy. Many of my friends go searching for bluevine and other native milkweeds in rural Oklahoma if they have a lot of cats. I hope you’ll try raising. It takes a bit to get the hang of it, but it isn’t hard.

  7. I have a question for you. Since you have been hatching these monarchs have you noticed more coming back to your garden? Do they return to where they were born or do you think they go where the wind blows?

    1. Lisa, I can’t really tell because I haven’t tagged mine. I’m going to start tagging next year to get better stats about where my butterflies fly. However, I do know this. The female and male butterflies I release often mate, and then the females lay eggs in my garden along with other butterflies that visit. I get many more eggs now that I raise the butterflies. I also try to wait between collecting eggs, and I’m going to start checking other places for eggs to keep from having siblings mating. It’s something I don’t see anyone writing about, but I am concerned about it. You want the genetic pool to remain diverse. I’m assuming butterflies are like animals in this case, but I could be wrong on that.

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