Dead foliage and flowers on plant rob the remaining portions of the plant of essential nutrients for continued growth. Trimming a plant involves two types of pruning. Deadheading refers to the removal of spent flower blooms to encourage lower buds to open. The second type of trimming involves pinching back stems to stimulate new foliage and flower growth. Learning how to trim geraniums can provide the novice gardener the opportunity to see results from these simple techniques. Geraniums respond beautifully to proper trimming with increased blooms and long lasting flowers.
Place the plant in an area where the pot can be rotated easily to see all sides. If the geraniums live in a hanging planter, bring the pot down to eye level so you don't miss hidden dead flowers or stalks in the interior of the plant.
Examine the plant carefully to check for new growth and unopened buds. You want to leave these areas alone as much as possible. Look for area of little leaf growth. This situation is called legginess and can result from lack of pruning as well as lack of water.
Grasp the stem behind spent flower blooms between your thumbnail and forefinger (or middle finger depending on your comfort). Press the thumbnail into the plant stem until the flower breaks free. This simple deadheading technique takes a few minutes and can be done whenever you notice dead or dying flowers on the geranium. Deadheading sends the plant energy to new growth and blooms instead of dying flowers, stalks and the creation of seeds.
Trim back flower stalks to the parent (main) stem using pruning clippers. Clip as close as possible to the main stem to leave only a small wound on the stalk. This maintenance trimming often stimulates a new round of blooms on the geranium.
Prune out dead or dying foliage to the nearest branch or set of leaves. This type of pruning also encourages fuller growth in the foliage areas of the plant, creating a bushier plant since the natural response of a plant involves sending out new shoots below the cutting point.
Trim back leggy plants (long stems with few leaves) with a major pruning to remove about one-third of the foliage. This promotes plenty of new growth to allow the plant to recover and flourish with healthy new shoots. Choose individual stems at regular intervals throughout the plant for uniformity. Clip back to the main plant stem.