Removing spent blooms is the best way to be sure that geraniums will continue to bloom throughout the growing season. If blooms aren't removed, the geranium's energy will be diverted to seed production. Development of new blooms will be drastically reduced, and the blooming season will be considerably shorter. Removing blooms will also keep geraniums looking lush, healthy, and neatly groomed.
Develop a habit of clipping off spent geraniums as soon as they fade. Once it becomes routine, it will require only a few minutes each day.
Cut back spent geraniums slightly above where the bloom attached to the main stem. You can use clippers, or simply pinch the bloom off with your fingers. Don't pull the bloom off, because it will wound the stem and leave an opening for disease or insects.
Throw the spent bloom on the compost heap. If you notice any disease or insect damage, bag the discarded blooms and put them in the garbage.