Lemon verbena, known botanically as Aloysia citrodora, is a woody shrub that brings a strong, uplifting citrus fragrance to any garden space. This deciduous plant, native to South America, is cherished for its aromatic leaves and refreshing aroma.
Growing and Caring for Lemon Verbena
Light Requirements
Lemon verbena thrives in full sun, requiring at least six to eight hours of direct sunlight daily for intense flavor and robust growth. Insufficient light leads to leggy, spindly growth and reduced leaf production. Indoors, supplemental artificial lighting may be necessary.
Soil and Nutrition
This herb prefers rich, well-draining soil and moderately fertile conditions. A slightly acidic to neutral soil pH (6.0-7.0) supports healthy development. Lemon verbena benefits from regular feeding; apply an all-purpose fertilizer in spring and compost tea during the growing season to maintain vigor and lush foliage.
Watering Needs
Consistent moisture benefits lemon verbena, but it is sensitive to overwatering, which causes root rot. Allow the soil to dry slightly between waterings, aiming for a moisture level similar to a wrung-out sponge. During the active growing season in spring and summer, water twice a week, ensuring deep saturation of the root zone. Yellowing lower leaves indicate overwatering, while dry, brittle leaves signal underwatering.
Pruning for Health and Shape
Pruning lemon verbena promotes bushier growth and maintains its shape. The ideal time for a significant prune is early spring, as new growth emerges, encouraging a fuller plant. Throughout the growing season, pinch off the top inch of new growth tips above a leaf node to redirect energy into lateral branching. Regular harvesting also prunes the plant, encouraging continuous new leaf production and preventing legginess.
Harvesting and Using Lemon Verbena
Optimal Harvesting Techniques
Harvest lemon verbena leaves in the morning, after dew evaporates but before the day’s full heat, when essential oils are most concentrated. Snip stems rather than plucking individual leaves, cutting back to a leaf node to encourage regrowth. For larger harvests, remove up to one-quarter to one-half of the plant’s height; the plant will rebound. Leaves can be dried by hanging in bundles, using a dehydrator (95-115°F), or microwaving until brittle.
Culinary Applications
Lemon verbena offers a distinct lemon flavor without tartness, making it a versatile kitchen ingredient. Its leaves infuse teas, cocktails, and other beverages, providing a refreshing citrus note. It flavors desserts like custards, sorbets, and baked goods, or savory dishes such as marinades for fish and poultry. For maximum flavor, add it at the end of cooking or use fresh, as high temperatures diminish its delicate taste.
Aromatic and Medicinal Benefits
Beyond culinary uses, lemon verbena is valued for its aromatic qualities. Fresh or dried leaves contribute fragrance to potpourri and sachets. Its essential oil is used in body products, including soaps and lotions. Traditionally, lemon verbena has been used to aid digestion, reduce fevers, and promote relaxation due to its calming properties, though scientific evidence varies.
Propagation and Winter Care
Propagating New Plants
Lemon verbena propagates effectively from stem cuttings, particularly semi-ripe cuttings taken in summer. Snip a 4 to 6-inch, flower-free cutting just above a leaf node. After removing lower leaves, insert the cutting about an inch deep into moist, sterile potting mix. Providing a humid environment, like covering with a clear plastic bag, helps cuttings root within a few weeks.
Preparing for Winter Dormancy
Lemon verbena is a tender perennial entering dormancy when temperatures drop below 40°F, often causing leaf drop. In colder climates (USDA zones 7 and below), grow plants in containers for indoor winter protection. Before bringing plants inside, reduce watering for a few weeks to prepare them for dormancy. Indoors, water minimally, and keep plants in a cool, dark location or a bright window; leaf loss is common. For plants outdoors in marginally hardy zones (8-11), cut them back and apply a 4 to 5-inch mulch layer for winter protection.
Common Issues and Troubleshooting
Lemon verbena is robust, but issues can arise. Spider mites and whiteflies are common pests, especially when plants are brought indoors for winter or are stressed by low humidity or insufficient light. Misting plants frequently deters spider mites, and insecticidal soap manages whitefly and aphid infestations. Yellowing leaves signal nutrient deficiencies, overwatering, or pest activity.
Overwatering frequently causes distress, leading to root rot when soil remains saturated. Ensure well-draining soil and allow the top two inches to dry between waterings to prevent this. Leggy growth results from inadequate light, prompting the plant to stretch towards a light source. Move the plant to a brighter location or implement regular pinching and pruning for a more compact, bushy form.