I plant Butterfly Milkweed (Asclepias tuberosa) to support Monarch Butterflies. I’d plant it for Large Milkweed Bugs alone, now that I know about these bright orange and black insects.

The Large Milkweed Bugs (Oncopeltus fasciatus) have multiple different forms in their lives:

  • As adults, they have wings and bold black patches on their backs, as shown in the top photo
  • Five (five!) wingless nymph stages, at least three of which you can see above
  • Round orange eggs on milkweed pods

They transition between the nymph or instar phases by popping off their hard shell and growing a new one. Each time, they get bigger, have more markings, and are shaped more like adults.

So many bright-orange nymphs cover the pods that it’s as colorful as another bloom cycle. Unlike their relatives the Small Milkweed Bugs, the large ones eat only plants, with a preference for Milkweed of course.

Last week, I spotted two adult bugs mating! They took their time, so I was able to get my camera for the photo below.

Large Milkweed Bugs mating , end to end, on Butterfly Milkweed flowerbuds.

The adult Large Milkweed Bugs fly around the garden. Their bright color, size, and leisurely speed makes them seem like daytime Lightning Bugs.

Orange Butterfly Milkweed flowers with Downy Woodmint, one of my favorite combinations

Want to Learn More?