I’ve been telling you that we can help Monarch butterflies in our Ecosystem Gardens by planting more milkweed because that is the only plant that Monarch will lay their eggs on.

We’ve also talked about making your wildlife garden a certified Monarch Waystation, which will provide habitat for them, since habitat loss is one of the largest contributors to their declining populations.

Monarch Caterpillars on Tropical Milkweed

And we’ve talked about
the amazing phenomenon that is the Monarch migration to their wintering sites in Mexico, and the scientists who study this migration.

Each time we’ve talked about Monarch Butterflies, I’ve told you about the need to plant more milkweed to help the Monarchs on this journey.

But I just received this comment here at Ecosystem Gardening that seems to suggest that Monarch caterpillars eat other plants besides milkweed:

Hi Carole: I was perusing around searching for more info on plant attractants for hummers and butterflies.
I read your information about milkweeds for monarchs and that milkweed was the only plant they lay their eggs on – to which I would have agreed until last Fall. I was pulling out my tomato plants upon the finishing of the growing season. Was fortunate enough to spot a beautiful green crysallis (sp?) on one as I was throwing it away. I took it off, along with the twig it was on, found a large old clean mayonnaise jar, punched holes in the top and layed the twig inside. I searched all my butterfly books and ascertained it was a monarch crysallis and promptly went on with my busy life, basically forgetting about it. I wish I knew how many days went by when my husband said “What are you doing with this butterfly in a jar?” I said, “What butterfly”? Oh, my goodness, Carole, it was the most beautiful Monarch I have ever seen. I tell everyone you haven’t seen a Monarch until you’ve seen one ‘just born’!!! Anyway, that dispels the info that we have always learned that they lay eggs ONLY on milkweed (which I have a LOT of). Interesting, huh? Knew you would get a kick out of this. Peggy from Connecticut

So, are we now to think that Monarch caterpillars eat tomato plants because we have found a chrysalis there? Does this dispel everything we’ve learned about Monarchs up to this point?

Actually, no.

Monarch caterpillars do only eat plants in the Milkweed family (Asclepias spp), so if we want to help them out in our wildlife gardens, we still need to add these plants to our gardens.

Monarch caterpillars do not feed on tomato plants, despite what may seem like circumstantial evidence to the contrary.

Monarch Caterpillar in Search of a Safe Place to Become a Chrysalis

What happens is this: when a Monarch caterpillar is ready to enter the chrysalis stage of its life cycle, it will leave the milkweed plants that it has been feeding on and travel (often quite a distance) to a place where it feels safe from birds and other predators.

Once the caterpillar finds a safe place, it will assume the “J” position and begin the process of transforming into the chrysalis phase.

Sometimes this safe place will be under a ladder rung, sometimes it will be beneath your air conditioner, or under your window sill. And as Peggy has discovered, sometimes this place will be under a leaf of your tomato plants.

Pretty cool, eh?

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Do Monarch Caterpillars Eat Anything Besides Milkweed SKU UPC Model

Swallowtail Caterpillar

Sep 19, 2017 by Christina Porter

I think some people might be mistaking the black swallowtail caterpillar for the monarch caterpillar. Black swallowtails eat parsley, fennel, and dill. I have seen plenty of black swallowtails on those herbs but never a monarch.

monarch caterpillar food

Aug 30, 2017 by Julie Free Free Heart

I have two parsley plants that have four or more Monarch caterpillars eating them to the quick. I was glad to share!


Aug 12, 2017 by Audrey

I came to your site because after years of collecting and sharing monarch eggs and caterpillars, and enjoying my butterfly garden, complete with milkweed, I found a full grown monarch caterpillar on my potted verbena flowers. That pot is quite a distance from any milkweed. I see in your article that they can travel a distance from their host plant to pupate. Thank you for the info. And in response to the previous comments, I have found many caterpillars on my parsley as well, but they are Black Swallowtail butterflies.

They eat Dill too

Aug 09, 2017 by joanne

As my Dill plant is slowly being entirely consumed by ONE monarch caterpillar, I was hoping to find other things for it to munch on so I could watch it turn into a butterfly. They definitely do not "only" eat milkweed, as this is the second year for me to have caterpillars on dill plants. Previous year there were 8!


Jul 29, 2017 by Teresa

I have them eating my fennel plant 2 yeaars in a row now.. As others have commented my fennel is almost gone and I have some pretty small caterpillars. What else can I provide for them to eat?

Monarch butterfly

Jul 20, 2017 by Leslie Verner

I saw your post regarding Monarch caterpillars eating only milkweed. As I type I have five caterpillars eating my Italian parsley plant down to the base of the plant. It's pretty much eaten and I'm not sure that they are finished growing.

May 16, 2017 by Patty

Cucumbers and pumpkins but must be fresh

4.4 5.0 7 7 I think some people might be mistaking the black swallowtail caterpillar for the monarch caterpillar. Black swallowtails eat parsley, fennel, and dill. I have seen plenty of blac Do Monarch Caterpillars Eat Anything Besides Milkweed