You don't say when you planted it this year. This one flowers twice, once around May and again later on, around September, with smaller flowers. Depending on when it was planted, and the size of plant it was, it may be that you missed the earlier flowers, or it wasn't big enough to produce flowers, but may do so later on.

You also give no information about where you've planted it (ground, pot) and the conditions (sun, shade), nor your watering regime, nor even where you are in the world, so more information would mean a better answer.