Both, actually! Putting Jerry Garcia aside for the moment, deadheading in your garden is an essential but simple task that results in more and better blooms for your flowers.
The reasoning behind why deadheading is so effective is simple. When a flower that has died remains on its stalk, the plant (not knowing the flower is dead) continues to send nutrients through the stalk. But when you remove that flower head, the plant stops wasting all that energy and vitamins on a dead bloom and redirects it instead to where it is needed – the healthy, blooming ones. So it makes sense that by deadheading (removing spent flowers) your plant will grow more and healthier blooms!
Now don’t just go haywire and start randomly ripping things out – there is a right way to do this. Put your thumb and forefinger directly below the spent bloom, on the stalk. Follow it down until it reaches the end of the stalk or the first elbow joint. THAT is where you want to pinch. Just talking the head off may not be enough for the stalk to know to stop sending nutrients and water in that direction. Plus it makes a prettier plant if you don’t have a bunch of headless stalks all over it! Even the popular Supertunias and Wave Petunias are famous for not needing deadheading, face it – they, too, look and perform better if you take the trouble to PINCH! away spent blooms!
ANOTHER TIP TO ENCOURAGE BLOOMS: Remember to fertilize your summer annual flowers often so they will continue to produce new blooms. If nutrients are in short supply, you will have significantly fewer blooms.