Fortunately, it isn't being sent from the U.K. as Postal Rates for shipping from there used to be extremely costly! Too bad you can't have them sent them by Priority, as it may be triple digit temperatures in Arizona & plants can actually get baked- even cacti ! ( unless, of course, the carrier uses A/C.)
Try calling the Inspection Station in Nogales, Arizona, to find out what they suggest. They may offer better solutions or give advice as to how to best handle the situation before transaction..
I would have those labels you send to France, Tracked. & maybe Registered..just to help avoid loss & or delays...
I do recall, some people, would get confused, over the labels system stickers, & accidentally mix them up, between what was to be affixed to parcel & included inside, but maybe it is much easier & less confusing, now days.
