Lemon verbena (Aloysia citriodora) is a cherished herb known for its strong lemon scent and versatile culinary and aromatic uses. This woody shrub can be a fragrant addition to a garden or container. Proper pruning is important to ensure lemon verbena remains healthy, vigorous, and productive.
Benefits of Pruning Lemon Verbena
Pruning lemon verbena offers several advantages, contributing to the plant’s overall well-being. Regular trimming stimulates new shoot growth, enhancing the plant’s aromatic qualities. This practice encourages a bushier, more compact growth habit by promoting lateral branching, preventing the plant from becoming leggy.
Improved air circulation helps deter fungal diseases and pests. Maintaining a desirable shape and size is useful for container-grown plants, ensuring manageability. Consistent pruning invigorates older plants, supporting their longevity and continuous production.
Best Time to Prune Lemon Verbena
Late winter or early spring is the most effective period for main pruning. This primary cut should occur just before new growth emerges, allowing the plant to recover and produce strong, fresh shoots. In colder regions, wait until the risk of frost has passed, as pruning wounds can make the plant susceptible to cold damage.
Throughout the growing season, lighter pruning, or “pinching back,” encourages continuous bushiness and prevents legginess. This ongoing maintenance helps maintain the plant’s shape and vigor. Avoid heavy pruning late in the growing season, especially in cold winter climates, as this can stunt growth and compromise the plant’s ability to withstand colder temperatures.
Techniques for Pruning Lemon Verbena
Effective pruning involves a combination of techniques throughout the year to foster robust growth and a desirable form. For initial hard pruning in late winter or early spring, cut woody stems back by one-third to one-half of their length. This encourages strong, new growth from the base and rejuvenates older plants. Always make cuts just above a leaf node or emerging branch, using sharp, clean pruning shears to ensure clean cuts and prevent disease.
During the active growing season, regularly pinching back the tips of young stems promotes lateral branching, leading to a denser, bushier plant. This involves snipping or pinching off the top inch or two of new growth. Harvesting leaves also functions as a form of pruning, as removing stems encourages more foliage.
When harvesting, cut stems just above a leaf or node, ensuring not to remove more than one-quarter of the plant’s stems at once. Deadheading, or removing spent flower stalks, redirects the plant’s energy towards leaf production rather than seed development. For overall shaping, selectively remove dead, damaged, or crossing branches to maintain an open structure and improve air circulation.
Post-Pruning Care for Lemon Verbena
Following any pruning, especially substantial cuts, appropriate care helps lemon verbena recover and thrive. After pruning, water the plant thoroughly, particularly after heavy trimming or in warm, dry weather. This helps alleviate stress and supports new growth.
A light application of a balanced, nitrogen-rich fertilizer supports the vigorous new growth that pruning stimulates. However, if the plant was recently repotted or the soil refreshed, wait a few weeks before fertilizing. If heavy pruning was performed in early spring in an area prone to late frosts, monitor weather and provide protection if temperatures are expected to drop significantly. Continuously observing the plant for signs of new shoots and health ensures it responds well to pruning.