Foodplants
There are two types of foodplant important to the survival of the butterflies in the garden – nectar foodplants for the adult butterflies to feed from and larval foodplants for the caterpillars.
A few plants actually double up as both nectar plants and larval foodplants. I call these VIPs: very important plants, being as they are performing both the tasks needed to keep our butterflies happy. Two good examples of VIPs are bird's-foot trefoil and dame's violet.