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Take a look at the plant from all angles so you can identify problem areas. Look for areas where there aren't many leaves, dead areas, and lopsided areas. Determine where you'll need to prune in order to give your geranium a healthier and more attractive shape. Pruning actually spurs new growth of stems and flowers, so trimming back a particular place won't necessarily leave a hole. If a large part of the plant is dead, you'll need to do some drastic trimming. The plant should survive as long as the central stalk is still green. However, it might take a few weeks before new leaves and flowers emerge. This pruning method is an important way to encourage the plant to create new flowers. Taking off the dead blossoms allows the geranium to direct energy toward producing new ones. It also clears your view of the plant's stalks, so you can better see what you're working with. You can deadhead your geranium any time you see languishing blossoms; it's a quick way to maintain the health of the plant, and doesn't even require tools. Grasp the flower stem just behind the dead blossom with your thumb and forefinger. Pinch the stem and sever it with your thumbnail, then discard the dead flower. Alternatively, you may want to wait until a whole flower cluster is spent, then remove the whole cluster further down the stem down at the next leafy area. The next step is to get rid of dead or dying leaves and stems. Trimming them back will keep the plant from wasting energy trying to keep them alive. Use a pair of hand clippers to trim dead or dying stems to the base of the plant. This is an important step to take in the spring in order to encourage good growth during the growing season, but you can trim back dead foliage any time of year. Don't bother trying to save foliage that seems on the verge of being dead, even if it's not quite there yet. It's better to trim it back and let the plant produce strong, new stems. In the spring, trimming back healthy flower stems will encourage the plant to produce more flowers. Follow a flower stem to where it's joined to the main stem, then use a pair of hand clippers to trim it against the base of the main stem. This will activate dormant buds and you should see new growth in no time. If you don't want to make such a drastic cut, follow the flower stem back to 14 inch (0.6cm) above the top of a node, which is a ring around the stem on a geranium. The new growth will sprout from the node. "Leggy" stalks refer to those that have grown long and tall without any leaves, or with just a few leaves. Trimming these back almost to the base of the plant will allow it to produce new growth low down, creating a fuller, bushier look. Use a pair of hand trimmers to cut the stems close to the base, 14 inch (0.6cm) above the lowest node. Keep the cuttings for propagation! At the end of the growing season, trim back at least 1/3 of the plant in this way to prepare it for winter dormancy.
Examine the plant. Deadhead the spent blossoms. Remove dead foliage. Trim healthy flower stems. Trim back leggy stalks.