Viola flowering time ?

My only late winter/spring plantings are a few trays of Violas and Pansies from the local nursery. I plant up a few containers and they flower really well intil May when I replant with my summer plantings . My question is how long would violas/pansies flower for if left planted ? Would they go through to September say ?

 

Morning HarryS ​

When their full flush of flower is over....yes, around May.....I cut violas hard back. They then resume flowering throughout summer. I tickle fish blood and bone around them at the same time. I divide the odd viola too after flowering, pot up and grow on.
Pansies? I regard these as "annuals" and throw them out after flowering.
(I also cut any flowers off newly purchased violas encouraging them to make growth at this time)

 

I'll plant up some Violas and cut back after the first flush of flowers and see if I can get the summer out of them. As you I always remove flowers from most early plants when planting to encourage growth not flowers at the early stage.