Is it necessary to deadhead petunias?

dead heading promotes more blooms and looks nicer than having those poor dead flowers in the mix.

Yes remove the spent flowers to eliminate insects possibility and gain more flowers.

I make certain that I take off the dead flowers every morning. Not necessarily dead heading, however. I've actually wondered the same thing, instead of just removing the dead flower, should I remove that entire "stem", if you will? Mine do quite well though and have spread quite a bit.

I deadhead all flowering plants. There should have been a plant pic inside the container giving the name and planting / placement instructions. The "Better Homes & Gardens" container is just supposed to be a better, healthier or fancier variety of any plant v. a "no name" or generic variety plant.

as pretty as petunias look, they will work you to death! you never get a day off! I almost got a DEAD HEAD MYSELF!! i finally changed to something else. all i wanted was color anyway.