Our commonest butterfly active from April to late September in three generations (although two is more likely here). Found over open landscapes, preferring damp ground. The food-plants are crucifers like cuckoo flower (Cardamine pratensis) and mustard plants in the family Brassicaceae.

References: 
Kirkland, P. (2022). Discovering Scotland's Butterflies.
Newland, D.E. (2006). Discover Butterflies in Britain.