Lantana is a popular garden plant known for its vibrant, continuous blooms that attract pollinators. While generally low-maintenance, many gardeners find their lantana plants fail to flower as expected. A non-blooming lantana often indicates an imbalance in its growing conditions or care. Understanding its specific needs can help diagnose and resolve these issues, encouraging abundant flowering. This article explores common reasons why lantana might not bloom and provides practical solutions to restore its floral display.
Sunlight Requirements
Lantana is a sun-loving plant that thrives with at least six hours of direct sunlight daily for optimal flowering. Some varieties may perform even better with eight or more hours of sun exposure. Inadequate light leads to leggy growth, sparse foliage, and significantly reduced or absent blooms.
To address this, assess your lantana’s current location. If in a container, move it to a sunnier spot. For in-ground plants, consider if nearby trees or shrubs are casting more shade. Pruning obstructing plants or transplanting the lantana can ensure it receives necessary sunlight for prolific blooming.
Watering and Fertilization
Proper watering and fertilization are crucial for encouraging lantana to bloom. Lantana prefers consistently moist soil but is drought-tolerant once established. Overwatering causes root rot, stressing the plant and inhibiting blooming, while severe underwatering also reduces vigor. Water thoroughly once a week, allowing the top few inches of soil to dry between waterings; container plants may need more frequent watering.
Too much nitrogen in fertilizers promotes leafy growth over flowers. To encourage blooms, use a balanced fertilizer, such as a 10-10-10 or 20-20-20 NPK ratio, or one higher in phosphorus and potassium. For in-ground plants, a light application in early spring is usually sufficient. Container plants benefit from monthly fertilization with a balanced, slow-release or water-soluble product due to nutrient leaching. Avoid over-fertilizing, which can lead to weak plants and reduced blooms.
Pruning for Blooms
Correct pruning stimulates continuous blooming. Deadheading, the removal of spent flowers, is important because it prevents the plant from expending energy on seed production. Leaving old flower heads diverts energy to berry production instead of new flower formation. Regularly removing faded blooms encourages more flowers and maintains a vibrant display.
General pruning for shape and size also promotes prolific flowering. Lantana blooms on new growth, so selective pruning encourages fresh stems. Cutting back stems by about one-third after a flush of flowering stimulates new growth and subsequent blooms. For perennial lantanas, a significant prune in late winter or early spring, cutting stems back to 6 to 12 inches from the ground, removes old growth and fosters a strong, bushy form with abundant flowers.
Other Factors Affecting Blooming
Several other factors can contribute to reduced lantana blooming. Temperature stress, like unexpected cold snaps, impacts these warm-weather plants. Prolonged cold temperatures below 28°F can damage or kill the plant, halting blooming. Protect the plant during colder periods or bring container plants indoors.
Severe pest infestations or diseases also weaken the plant, diverting energy from flower production. Pests like lace bugs, whiteflies, aphids, and spider mites feed on plant sap, causing discolored leaves, stunted growth, and reduced vigor. Regular inspection and prompt treatment help the plant recover and resume blooming.
If a potted lantana becomes root-bound, its vigor and blooming can be inhibited. Repotting into a larger container with adequate drainage can alleviate this stress and revitalize the plant.
Additionally, very young lantana plants need time to establish a robust root system and foliage before producing many flowers. Patience and consistent care during this establishment phase are important for future blooming success.