Marguerite or Purple Ronnies
Daisy is the name applied to many flowers of the Asteraceae or Compositae family. Flowers in this group include Aster, Bellis daisy, or Sunflower family plus Chrysanthemum, Gerbera, Calendula, Dendranthema, Argyranthemum, Dahlia, Tagetes, Zinnia even Lettuce and many others.
Marguerite is botanically called Chrysanthemum frutescens meaning shrubby. Native to the Canary Isles, they have been cultivated in England since 1699 as a white and sometimes pink flower.
These plants are especially common in open and dry environments where these purple plants were found.
The yellow centre attracts all the pollinating insects that the plant needs to reproduce seed.