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.