You do not need to pinch the blooms. You can prune it back if you want to keep to a size you like.

lantana truly is the original (almost) no maintenance plant. If you give it what it needs: halfway decent soil, WARM soil, full sun, and moderate amounts of moisture, you will have nothing to do but enjoy it. Like Wally, mine get so large later in the summer, that I have to take the pruners to them to keep them in bounds, but otherwise, they do not need pruning. They'll be plenty bushy all by themselves.

Thanks!