The Small White is a highly mobile species and each year the resident population is boosted by individuals flying in from mainland Europe.  It is a common visitor to gardens where it breeds on brassicas and Nasturtium, though it relies less on cultivated brassica crops than the Large White and breeds on a range of wild foodplants.  Adult butterflies are attracted to white flowers where they feed and on which they are well camouflaged when roosting.  This is a common and widespread species.