I'm sorry to hear about your problem. I became aware that this would happen in 2017, not might happen, unless the govt took steps to avoid it. That they didn't amounts to criminal negligence in my view. It isn't only a matter of stuff subject to 3rd country sanitary & phytosanitary regulations, but loads, & I mean many, many, other areas of economic activity will run into walls like this as a result of the insane decision to leave the single market.

My point is if I, an ordinary citizen, could know about this 3yrs ago why haven't professional journalists. I know it's a bit nerdy to delve into the workings of the EU treaties as well as being terminally boring, & a part of my job involves ferreting out information, but none of this is or was a secret, nor difficult to find.

It's the duty of the media to identify things vital to the national interest & to present them in such a way as they become understandable to the general public, not to mention those politicians who don't have the benefit of access to civil service advisors. They have failed in that duty, which means one of the institutions which support our system & keep our society functioning properly has failed.

That's really serious.

You're probably right in your other post about an element of nostalgia coming into the leave vote, but for most people I believe it was a protest against the political class having ignored their concerns, especially around immigration, for the last half century. No-one voted to leave the single market; that was Theresa May's doing without so much as a word of debate.

It was entirely possible to leave the political structure of the EU whilst staying in the single market, which is what I thought I was voting for, & had it been even hinted that that could happen I would probably, reluctantly, have voted remain.

The ironies mount up though. You mention T. Blair's ambitions for decentralising govt. Well, he did manage Scottish devolution, but getting down to the local level was impossible because that was opposite to the EU's political direction of travel. Did he not know that at the time. We don't know. Now though it would be possible, though highly unlikely as long as the present crew remain in power.

You'll probably need an import agent in order to get your stuff into France, but as far as I'm aware he/she doesn't need to be a specialist, just a resident, not neccessarily of France only, but you'd need to check that. In other words a friend or relative could do it without payment. Of course they would then be legally liable should one of your seedlings turn out to be a triffid. 

At least, unlike lobsters for example, a couple of days sat on a dockside aren't going to make your enterprise impossible.