Peak parsley

Round about now,  the cow parsley reaches is its apotheosis and our access lane becomes a bridal avenue for the Queen on May. The creamy blossom combines with red campion and stitchwort to create an almost luminous floral haze. It is a wonder to behold -  and to remind ourselves that in a very few weeks we will curse the same plant's collapse into messy straggles of soggy leaf and stem.

I call it cow parsley, some call it keck, or dog's flourish, or... mother-die, and if you want to know why see here.
What do you call it?