Transporting blooms is always an iffy proposition. Years ago I exhibited a few times in a daylily show, for which I had to drive about 2 hours. I tried various ways... putting scapes into bottles, then into 6 packs but only 3 bottles per 6-pack - but then you have to secure that 6-pack from moving around..... putting scapes into bottles in a 5 gal garden pail (but you still have to keep those scapes separated and you still have to keep the pail from moving around), and so forth. Finally I had DH build me a PVC contraption, but it was awkward and took up the whole back of the SUV, and I think that it leaked...
At least I learned how to groom daylilies for exhibition. I'm afraid that I still don't quite understand what needs to be done for irises, nor how to predict if something is going to be open the next morning, and/or will last the two days of the show.
I'm trying to imagine what pieces of styrofoam you are talking about (that have holes in them, to put into the bottom of a pail or bucket), but I can't visualize them.
I had plans to go to the art show today, Jan, but I was just too tired. Maybe tomorrow; sorry that I will miss seeing you there. Sorry, too, that you had to miss your iris show.