14 Oct Flora vs. Fauna: Frisky Butterflies, and When Caterpillars Get the Munchies

This year, our passion flower vine — at long last — started blooming like nobody’s business.

Until the gulf fritillaries moved in. There’s a reason why these bright orange insects are also called passion butterflies: the Passiflora is the only plant on which they meet, mate and lay their eggs.

At first, it was sublime. Who wouldn’t want to walk into their yard and into an amber cloud of butterflies? But by late September, the butterflies had turned our passion flower vine into their own private love motel. (Passiflora are coursing with cyanogenic glycosides, which are poisonous to all caterpillars species except the zebra longwing and our abovementioned flapping frenemies.)

In fact, when C’s mom (!) was in town, we even caught a couple of adult butterflies in flagrante delicto:

“I think that one’s dead,” C’s mom said about the butterfly at the bottom (or on top?) of the coupling.  Turns out, it was only catatonic during the mating process (ed: there’s an Ambien joke in here somewhere…) because the pair eventually flew off, leaving eggs in their wake.

The eggs hatched within a few days. And the larva that inched out was hongry.

It’s worth noting that these caterpillars won’t actually destroy your passion flower — they’re important pollinators, actually. So it’s not advisable to evict every caterpillar with the munchies who shows up on your vine. But if you’ve reached your limit for Swiss-cheese foliage, there are some elegant, non-chemical fixes available. For example: using a hose at medium pressure to wash off the eggs and insects, or donning gloves and removing the spiny guys by hand, or setting up a bird bath or bird house nearby and letting the food chain have at it.

What did we end up doing? For several weeks, we let the caterpillars hang out and do some of our pruning for us before they pupated. Once many of the chrysalises (which resemble dead leaves, a way to dupe predators) had been abandoned by newly minted butterflies, we drastically cut back the plant, all the way to its original stalk. An anticlimactic solution, but one that could lead to vigorous regrowth next year. Maybe next year we’ll even get some fruit!