Buddlea and verbena, both good butterfly plants, have both started to bloom in my garden. I haven't seen any butterflies on the buddlea yet, but there are on verbena...
There are many more in grass...
On GW on Friday night, Carol Klein showed us cranesbills growing in grass. This is a cranesbill in grass, with butterfly drinking nectar...
Here's a very uncommon one, resting on a log, in grass... 
Cheeky Robin...