Wild flower meadow

I have a 4m x 4m area which I am trying to convert to a wild flower meadow but living in an area of grade 1 agricultural land, specialist turf just went to grass despite the addition of yellow rattle. I am limited to the depth of soil I can remove by snowdrops and naturalised narcissus pseudonarcissus. Any ideas as how to impoverish the soil would be very welcome.

As a former conservation land manager, I can only say that you should cut as often as you can and rake off.

and stick with the yellow rattle.