Deadheading for Height Growth

Overview

A flowering plant has one purpose during the growing season: producing seeds for the next generation of plants. Once a plant sets seed, it may stop blooming unless the spent bloom is removed in a technique called deadheading. This is especially true among perennial flowers and flowering shrubs.

Deadheading

Remove spent blooms from the plant with a set of garden shears or sharp scissors. Note how the plant grows; flowers produced by themselves on a stem without leaves should have the entire stem removed. Marigolds are a good example of this kind of flower. Flowers on stems that include leaves should be cut above, but close to a leaf node.

Height Habit

Force plants with flowers on leafy stems to grow higher. Prune back the flower stalk near the top of the stalk, rather than lower. The plant will push out new stalks from the original which will have several leaf nodes before the flower head. This results in a plant that is higher, rather than bushy. Some plants will be unable to support the multiple flower heads on their own and require staking or caging.

Bush Habit

Deadheading will create a plant that produces more blooms. Pruning a spent bloom from a plant will cause the stalk to divide and produce two blooms where there was only one bloom before. Prune those two flowers and the stalk will produce four more. In this manner, a bushy plant is produced. Cutting the leafy flower stalk low, rather than high, produces a bush habit.

Wilting Flowers

Once flowers are pollinated, the plant will begin to shift towards maturing the seeds, rather than growing. Look for signs of pollination such as wilting flower heads on plants that have been receiving plenty of water. If a flower head begins to wilt, it has likely been pollinated and will begin seed maturation shortly. Prune these flowers off before the seeds mature.

Fresh Flowers

Cut flowers before they die or wilt and bring them inside for bouquets. The plant will produce more flowers and grow taller. Using the method for a height habit will produce plants that grow taller, rather than wider.

Shrub Roses

Grow your repeat blooming shrub roses by deadheading them throughout the summer. As the blooms die, follow the stem from the dead flower back to a five leaf node and clip it off at a 45-degree angle with a sharp shears. By choosing to deadhead only blooms at the top of the plant, you can encourage a taller plant, rather than one that forms a wider bush.