First 2 pictures are the same caterpillar, last one is the sibling. We have these caterpillars in an outdoor enclosure. They are feeding on a potted Asclepias purpurascens.

I've been trying to plant with specialist bees in mind, but I'll be expanding the milkweed area this fall/winter. The flowers bring in tons of pollinators and I would eventually like to do some mothing on the plants when my kid is older. Also I think the flowers are very fragrant and beautiful so there is ornamental value there.

As much as I think some milkweeds would be fun to grow such as showy milkweed, balloon plant, etc. I'm only planting with the ones naturally occurring in this region. I had read that the non native milkweeds could have unknown physiological changes on the things that use it. A study where caterpillars were fed tropical milkweed had a smaller wingspan as butterflies compared to the caterpillars who were fed common and swamp milkweed, so not good for migration. Also the amount of cardenolides vary between the species of milkweed which the caterpillars can sequester. There is not enough research on the non native (to NJ) milkweeds IMO.

Wow, on 7/25 these two caterpillars were just eggs about to hatch, and now they are already almost an inch long. I forgot how fast caterpillars can grow. I better hurry up and order the tags.

The first thing I noticed today were their poops, and I noticed how large the poops had gotten. When I found the caterpillars on the leaves they looked considerably larger than yesterday.

This is a fun little project to do with my kid. She loves the caterpillars. We'll definitely be doing this again next season.

A couple of weeks ago we had a big fat black swallowtail caterpillar and she liked petting it with her finger. She was touching it gently and it must have been gentle enough the caterpillar didn't mind it, because it didn't stick out the smelly orange horns at her.

That black swallowtail caterpillar was not in an enclosure and it had since left to make a chrysalis.