It's called the Plant Reproductive Material Law, and it attempts to put the government in charge of virtually all plants and seeds. Home gardeners who grow their own plants from non-regulated seeds would be considered criminals under this law.
The draft text of the law, which has already been amended several times due to a huge backlash from gardeners, is ◼ viewable here.
...While this law may initially only be targeted at commercial gardeners, it sets a precedent to sooner or later go after home gardeners and require them to abide by the same insane regulations....
RealSeeds.co.uk warns about any attempt to actually try to understand the law by reading it:
You cannot just read the first 5 pages or so that are an 'executive summary', and think you know what this law is about. The executive summary is NOT what will become the law. It is the actual Articles themselves that become law, the Summary has no legal standing and is just tacked on as an aid to the public and legislators, it is supposed to give background information and set the proposed legislation in context so people know what is going on and why.
The problem with this law has always been that the Summary says lots of nice fluffy things about preserving biodiversity, simplifying legislation, making things easier etc - things we all would love - but the Articles of the law actually do completely the opposite. And the Summary is not what becomes the law.