The answer depends on individual preference. If you like the look of the flowers (or want to harvest seeds) then leave them alone until they are done blooming.
If you think they are messy looking then cut them off.
Many people suggest that cutting the flower scapes off will encourage the plant to redirect more energy into growing roots and leaves which will result in a more vigorous plant.
Entered by caliloo
GardenWeb Home Page | Forums | Hosta Forum