Question
QUESTION: Should I deadhead my knock out roses when the petals on the flower have fallen off? If so, is it OK just to break off the head with my thumb or a scissors?  There is no way to dead head down to the next 5 leaved leaf on the stem as then I'd be removing all the flower buds that are up above that leaf.

ANSWER: It is no longer true that you have to cut down to five leaflets as that is a myth and has been disproven. It also isn't necessary to dead head Knock Out roses, but dead heading any rose always helps so simply snap them off with your fingers.

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QUESTION: Can you say more about the following comment you made: you said it isn't necessary to dead head knock out roses, yet at the same time you recommended I do it, since you said that deadheading any rose helps.  It's a lot of work to keep my 35 knock out roses and my 15 hybrid tea roses/grandiflora deadheaded (all of which I've been doing!), so I'd appreciate knowing how it helps, so I can decide whether to continue or not.  Thanks for your help.

Answer
A rose only blooms to make a flower which in turn becomes  seed case called a hip. Making seeds is the main purpose of the rose bush. After it has made the seed hips, it then can slow down or even stop producing flowers. Some classes of roses really do need to be dead headed if you want them to bloom more. Hybrid Teas and Floribundas are the two such classes ( Climbers as well)  that must be dead headed for more blooms. When you get into the Modern Shrub rose classification, most don't have to be dead headed because they produce such a large amount of flowers in comparison to the other two classes. There is now a new classification of roses called Landscape Roses or Shrubs, and they continuously produce flowers and so do not need to be dead headed and Knock Out is in this class. Again you can dead head if you want to, but you will probably not notice the difference in regards to the amount of blooms if you do. I was assuming you only had a few roses, but 35 is too many to be dead heading if it doesn't make a really big difference. Knock Outs were bred to be left alone and so cause no extra work.