If you want to grow bushier flower plants with more flowers, then remove the first flower bud or couple of buds and spent blooms. This works well for flowers that tend to grow long and lanky such as zinnias and chrysanthemums.
Removing the first flower bud before the plant blooms will encourage side branches to develop at the leaf intersections; therefore, increasing the bushiness of the plant. In addition, each new side branch will produce more flowers.
Deadheading
Also deadhead or remove spent flowers to encourage more flowers and a bushier plant. Deadheading will prolong the amount of time that your flower plants bloom. Deadheading chrysanthemums will provide you with another round or two of blooms. Deadheading roses will ensure that you have continual rose blossoms from late March to the frost.
I pinch instead of using scissors to deadhead. which is best?
You can use either one. If the bud is very close to the leaf I pinch, if there is more of a stem I use scissors because I find them easier and I don’t risk pulling the plant.