Lemon Verbena (Aloysia citrodora), also known as Cedrina, is an aromatic herb celebrated for its distinct lemon fragrance. Originating in South America (Argentina, Bolivia, and Paraguay), it arrived in Europe in the 17th century, cultivated for its essential oil.
Lemon Verbena grows as a deciduous shrub, reaching 7 to 10 feet in native tropical environments, but often stays 2 to 4 feet in containers. Its lance-shaped, glossy leaves release a strong lemon scent when bruised. Small white or pale lilac flowers may appear from mid-summer to early fall.
Growing Cedrina
Light Requirements
Lemon Verbena thrives in full sun, requiring at least six hours of direct sunlight daily. While it tolerates partial shade, insufficient light can cause leggy growth and reduce its lemon scent. Ample sunlight promotes denser foliage and vigor.
Soil and Potting
Well-draining soil is important for Lemon Verbena, preventing waterlogging that harms roots. An ideal mix is fertile and rich in organic matter. For in-ground planting, amend heavy clay soils with compost to improve drainage and nutrients. In pots, ensure drainage holes and use a quality potting mix. Lemon Verbena prefers mildly acidic to neutral pH soil.
Watering
Consistent moisture is important, but avoid soggy conditions. Water thoroughly when the top inch or two of soil is dry. Overwatering causes root rot; underwatering leads to wilting and stress. Container plants may need more frequent watering during hot, dry periods.
Temperature and Hardiness
Lemon Verbena is hardy in USDA Zones 8 to 10, surviving outdoors year-round. In colder climates with freezing temperatures, grow it as an annual or overwinter indoors. Indoors for winter, plants may become deciduous, losing leaves, and need minimal watering in a cool, bright location. Autumn mulching protects roots of in-ground plants in borderline zones.
Fertilization and Pruning
Lemon Verbena benefits from light fertilization during its active growing season (spring through summer). Apply a balanced liquid fertilizer at half strength every few weeks for healthy foliage. Avoid over-fertilizing, which reduces fragrance.
Regular pruning maintains shape, promotes bushier growth, and encourages new, fragrant leaves. Pinch back stem tips to encourage branching. In early spring, prune back previous year’s growth to a few buds on the woody framework. This rejuvenates the plant for robust new growth.
Harvesting and Using Cedrina
Harvesting Techniques
Harvest Lemon Verbena leaves in the morning after dew dries, when aromatic oils are most concentrated. Pinch off individual leaves or cut entire stems for larger harvests. Regular harvesting encourages bushier, more productive foliage.
Culinary Applications
Lemon Verbena’s intense lemon flavor makes it a versatile culinary ingredient. It infuses flavor into teas, beverages, and desserts like custards, sorbets, and syrups. Leaves also add a bright, citrusy note to savory dishes, including poultry, fish, and salads. Its flavor is distinct from citrus, offering a clean lemon taste without acidity or bitterness.
Other Uses
Beyond culinary uses, Lemon Verbena is valued for its aromatic properties. It is a popular component in potpourri, sachets, and home fragrances due to its long-lasting scent when dried. Its essential oil has been used in perfumes. It can also act as a natural insect repellent.
Propagating Cedrina
Propagate Lemon Verbena through stem cuttings. Take 4 to 6-inch softwood cuttings from healthy, non-flowering stems in late spring or early summer. Remove leaves from the bottom two inches and dip the cut end in rooting hormone, though this is not strictly necessary.
Root cuttings in water, changing it every few days, or directly in a well-draining potting mix. Plant cuttings in moist soil, ensuring at least one leaf node is beneath the surface. Place the pot in a warm location with indirect light and maintain consistent moisture until roots develop (typically a few weeks). Once roots form, transplant new plants to larger pots or their permanent outdoor location.
Common Problems and Solutions
Lemon Verbena is a resilient plant, but can encounter issues. Yellowing leaves often indicate overwatering (leading to root rot) or underwatering (causing drought stress); adjust watering practices to resolve this. Nutrient deficiencies can also cause yellowing; a light application of balanced fertilizer may help.
Pest infestations, like spider mites and whiteflies, can be managed by regular inspection and applying insecticidal soap or neem oil. Leggy growth (long, sparse stems) usually signals insufficient light or a need for more frequent pruning. Increasing light exposure and regular tip-pinching promotes a bushier, more compact growth.