When blooming begins, look for flowers that are declining in health. Do not wait more than a week to do so, as it is important that faded flowers are removed before the plant begins forming new seeds.
Use bypass pruners to remove unhealthy blossoms. If bypass pruners are not available, use your fingernails or a pair of scissors to remove them. To keep the plant aesthetically balanced, avoid cutting the crown. Cut as close to the base as you can. Gently move all of the flower bunches around to make sure that all of the dead or fading blossoms are accounted for.
Apply a balanced liquid fertilizer on a bi-weekly basis. Make sure that the fertilizer is made specifically for flowers. This helps the plant to thrive and produce robust blossoms.
Check the geranium plant regularly for spent blooms. Remove them whenever necessary until the plant is dead. Perennial geraniums are not affected by deadheading as much as annual geraniums.