I had a similar experience last year when I planted mine, which were quite small. I picked them off and raised them in tupperware boxes and then in a butterfly cage for their last instar. I supplemented the few leaves I had with some leaves from several bushes I know of in the woods near our house. They're everywhere since deer don't typically browse them. Alternately you could bring in some sassafras leaves.

If you want the bushes to get established and grow those first couple of years you can't let caterpillars defoliate them. So I'd suggest relocating them or raising them yourself.

I almost wish I had your problem. I ordered four spicebushes at least six years ago and they've been doing fine, but I've never seen Spicebush Swallowtail caterpillars on them. Yet, I see the butterflies around here mostly every summer. If you think that you can't get any bushes locally, I suppose that sending for them is no guarantee that the food will get there in time for the caterpillars before they're grown. If it were me, I'd try to find a spicebush or sassafras tree growing nearby and try to supplement their food supply. I suspect the butterflies around here must lay their eggs on sassafras trees (at least so far) and that is why I haven't found any cats on the spicebushes. I hope that you can raise the cats to maturity. From the pictures I've seen, they look like about the cutest kind of caterpillar. I've raised many different kinds, but not that one yet and also not Zebra Swallowtails. I have lots of plants here for lots of different kinds of butterflies. You will have lots of foliage eventually, but I'd be concerned that the cats will run out of food this year if you don't find some other source of food for them besides your small spicebush.Best of luck.

You can feed them sassafras leaves, they won't know the difference, and they'll thrive just as well as they do on spicebush leaves.

Sherry

Well the local [private] botanical garden was useless and I haven't been able to located any spice bush or sassafras locally.

I do have a bay laurel in a pot on my balcony. Would that work do you think? There is a tulip poplar in the woods near my house but it is very inaccessible.

1) An important one not yet mentioned is Camphor - Cinnamomum camphora.

2) I am very interested in knowing how they reacted to your giving them your
balcony plant.

3) "Based on laboratory feeding tests, Scriber et al. (1991) reported that
neonate Papilio troilus starved to death rather than initiating feeding on
non-lauraceous hosts (including ...tuliptree...."
http://entnemdept.ufl.edu/creatures/bfly/spicebush_swallowtail.htm

Four - in the end I let nature take its course. I tried to locate host plants without success, and after finishing off my spicebushes, the caterpillars moved off to somewhere (who knows where) else.

I did end up planting more spicebushes but of the tree extra I've planted, two have died, and one looks likely to follow. Because I have a stubborn streak, I'll put in still more this autumn and hope some survive. This year has been rough on my plantings for various reasons.

May I ask where you get your spice bush? Do you order them? I ordered 3 in Spring, just one came out of dormancy. The seller ( Etsy) shipped replacements. Once they emerged they are definitely not spice bush. Still trying to figure out what they are and if they are safe to plant in the ground. So I am not going to order more from there...

Is there a picture to help id it for you?

I do most of my plant purchases online. The first spicebushes I ordered were from Lazy S's Farm (my favourite online nursery), but they're out of stock, so the second order came from Jim Engel at White Oak Nursery.

Thank you. I did post a picture in the shrub forum, but here it is. I figure I will keep them in pots until I am sure.

Lindera benzoin is also available for order from Woodlanders Nursery in Aiken SC.

That's pretty close. Awesome! Somebody should stop me from planting all that stuff though. Spending a lot of time dragging the water hose around these days.

This was one of the things I came up with after looking at hundreds of Google images. But they seemed to have smooth leaves, mine have little teeth. Do yours? My best bet was really bladdernut. I can't believe the seller didn't even answer if that would be a possibility. I mean they should know what they have around.

Honestly though, either one would be fine with me. I am just a bit paranoid after fighting a single wisteria plant for the fourth year....