Deadheading, the act of removing spent flowers, is recommended to maximize the bloom production of geraniums (Pelargoniums). While the plant will survive without intervention, this simple task ensures a continuous display of color throughout the growing season. Deadheading forces the plant to allocate resources toward generating new flowers instead of maturing seeds.
The Physiological Reason for Deadheading
A plant’s primary biological objective is reproduction, meaning producing viable seeds. When a geranium flower fades, the plant redirects energy reserves toward developing a seed capsule. This natural process consumes a significant amount of the plant’s energy stores.
Removing the spent flower head before a seed develops halts this resource-intensive process. The energy used for seed maturation is instead redirected into vegetative growth and the initiation of new flower buds. This encourages a continuous cycle of repeat flowering, artificially extending the blooming period and resulting in a fuller, more abundant plant.
Step-by-Step Guide to Deadheading
The technique focuses on removing the entire flower stalk, not just the petals. Identify a spent flower head, which appears withered, discolored, or brown. Trace the slender flower stem, known as the pedicel, back down to the main stem.
The correct place for removal is where the pedicel meets a leaf node or the main stem, often characterized by a slightly bulbous joint. Use your thumb and forefinger to gently pinch and snap the stem cleanly at this point. Alternatively, sharp, clean shears or snips can be used to make a precise cut, which may reduce the risk of introducing disease.
It is important to remove the entire stalk. Leaving a portion causes the plant to expend energy maintaining the remaining tissue. Check the plants continuously, at least once or twice a week during the active blooming season, to ensure energy is available for the next flush of blooms.
Geranium Varieties That Require Less Maintenance
Manual deadheading is standard for traditional zonal and regal Pelargonium varieties, but certain modern cultivars require less effort. These are often referred to as “self-cleaning” geraniums. In these specialized varieties, the petals and spent flower heads naturally drop away before the plant invests resources into setting seed.
Self-cleaning types are common among single-flowered ivy geraniums (Pelargonium peltatum) and newer interspecific hybrids. Examples include the Caliente and Caldera series, which are bred to shed their spent blooms naturally. This trait allows the plant to bypass the need for manual removal, making them a popular choice for hanging baskets and window boxes.
These low-maintenance options are beneficial for gardeners with limited time or large numbers of container plants. However, even these varieties may benefit from occasional light tidying to remove any remaining pedicels or damaged foliage.