This Salsify is the same plant as the root vegetable. It is not strictly native, but introduced from the Mediterranean and naturalised in SE England. The root would be eaten after the first year’s growth, but if you leave it till the following year you get a beautiful ornamental flower so lovely to use in the flower garden, or meadow. It is a close relation of Goatsbeard but with a purple flower.
Salsify is also known as the Oyster plant as the roots have a similar flavour to Oysters when cooked! They can be used in a range of savoury dishes and even in cakes!