Supposedly.
The USDA (or whomever dictates all of this and lays down the law) obviously knows that there are countless "hobbyists" sending plants through the mail. (That is at least one reason why they gave up on the federal quarantine for daylily rust, or at least that is my understanding; they knew that that hobbyists were spreading it regardless.) That said, I never heard of anyone having to pay fines or anything, though a couple of times I had incoming plants interdicted here, and got strongly worded letters from the CA Dept. of Agriculture.
I made up one quart of Serenade and sprayed it around. It doesn't smell anywhere near as bad as comments I'd read led me to believe. It does say that you have to use the mix within 24 hours, and since we are supposedly getting rain tomorrow, I ended up spraying a lot more plants than I had intended, not to let it go to waste.
(Most daylilies here have some degree of resistance anyway, as most rust buckets get the boot, so it's not like the garden is a horror of rust.) So the spray went on a couple of rust buckets that I want to keep for particular reasons, a few others somewhat less rusty, and some recent acquisitions (because, who knows...).
