Monarch butterflies have made their way to Texas, but unfortunately not much milkweed greets them upon arrival.  A harsh, dry winter preceded by drought and schizophrenic weather have left the sought-after perennial a no-show in many Texas gardens–and on roadsides and ranch land.

Milkweeds, that is, any Asclepias species, are the host plants to Monarch butterflies and the only plant on which they will lay eggs to continue their life cycle.

Reliable DPLEX correspondent Harlen Aschen wrote to the listserv that reaches hundreds of butterfly fans that on a 1000-mile trip from Port Lavaca, Texas, past San Antonio to near Abilene and back around Austin “we saw no blooming milkweed.”

Not good.

Yet that hasn’t stopped a tenacious group of butterfly lovers from raising caterpillars and hatching butterflies on “alternative fuels.”

Professional butterfly breeders have been experimenting for years to keep their livestock well nourished when host plants become scarce.    Many of us who raise butterflies at home, especially in a year like this, also seek alternatives, since local nurseries seem to be having a hard time getting milkweed and keeping it in stock.

The recent news that the Monarch butterfly migration may soon become extinct because of a loss of milkweed habitat is driving the demand.

So what’s a hungry caterpillar to do?

Hungry caterpillars on milkweed seedlings

My boys are hungry! Six Monarch caterpillars have pretty much decimated this pot
of milkweed seedlings planted in February. Good thing I have another one.
Photo by Monika Maeckle

Monarch caterpillars eating pumpkin

No milkweed? No problem.
In the fifth instar, Monarch caterpillars will eat a variety of pumpkins.
Photo courtesy Ellen Reid

It’s a quandary.   At my house, I planted Tropical milkweed seeds in February and have several pots growing, including two filled with seedlings only two inches tall.  This will sate my caterpillars for a few days, at most.

I’m hoping that by the time the hungry cats finish up the tender seedlings, my garden milkweeds will have taken off.  Or perhaps local nurseries will get more milkweed in stock.
Over on the DPLEX list, butterfly buffs–and the Monarch caterpillars–are getting resourceful.  Several folks mentioned that by the time the caterpillars get to their fifth instar, or their final stage, before morphing into a chrysalis, they will eat pumpkin and cucumbers.

That’s right, folks.   See it with your own eyes.

PUmpkin fed Monarch

The Monarch butterfly on the left was fed with pumpkin during its final instar. Photo by Ellen Reid

“The butterfly on the left was fed with pumpkin during its final instar.  The one on the right was reared on milkweed,” Ellen Reid wrote via email all the way from St. Arnaud, Victoria, Australia.  “We couldn’t distinguish between them in any way.”  Reid shared a photo of “pumpkin frass”–orange colored butterfly poop which is produced in volumes in the final stages of the caterpillars metamorphosis.   Usually the frass is dark green or even brown, but “pumpkin frass” looks like the food that fueled it.

Pumpkin frass

The frass, or butterfly poop, of pumpkin fed Monarch caterpillars reflects the food’s orange tint.
Photo courtesy Ellen Reid

Paul Addington tried feeding his Monarch caterpillars cucumbers. It worked.  “These cats are eating the skin of the cucumber,” relayed Addington. “These were organic, but still felt like they were waxy, so [they were] heavily scrubbed first.” Addington said the caterpillars indeed preferred milkweed when given a choice. “All 52 of mine finished on cucumber, looked great and joined the wild,” he said, adding “UPDATE: must be fresh, crunchy cucumbers.…two-weeks-in-the-fridge cukes were rejected with enthusiasm….what an uproar!”

Dr. Chip Taylor, founder of Monarch Watch, chimed in to the conversation, letting folks know that the alternatives have been known for a while.

“These alternatives have been utilized by many people in the past. They only seem to work for fifth instar larvae that are less than four days from pupating. Many of the larvae will not make these transitions successfully.”

So Monarch butterfly caterpillars appear to be more adaptable than we thought.

Monarchs eating cucumbers

Monarch caterpillars in the fifth instar will eat cucumbers.
But they have to be FRESH cucumbers! Photo courtesy Paul Addington