South East county, Kent, has been referred to as The Garden of England for hundreds of years. With its spectacular coastline views and White Cliffs of Dover
www.travelaboutbritain.com
Yorkshire, North Yorkshire to be precise and not the whole of the county, was only referred to as Garden of England following a survey. In other words, it was based on the opinions of a selection of people, almost certainly northern monkeys, as opposed to the award of an official title.
On the basis of the foregoing, the Garden of England is indeed Kent. Fact.
As a side note, I have no dog in this fight. Both counties are bung holes and I wouldn’t willingly live in either.