Lavender (Lavandula spp.) is a drought-tolerant plant native to Mediterranean regions, thriving in well-drained, sandy, or gravelly soils. When the roots sit in waterlogged conditions, they suffocate due to lack of oxygen, leading to root rot. This manifests as yellowing or browning leaves, starting from the lower sections. Overwatering also promotes fungal diseases like Phytophthora, which further damages the root system. To prevent this, ensure your lavender is planted in fast-draining soil and watered sparingly—only when the top inch of soil is dry.
While lavender is drought-resistant, prolonged dryness can cause stress, especially in young plants or extreme heat. Underwatered lavender may develop brown, crispy leaves or yellowing due to dehydration. The plant conserves water by sacrificing older foliage, starting from the base. If the soil feels bone-dry and the plant appears wilted, increase watering frequency slightly, but avoid overcompensating. Mulching with gravel (not organic mulch) can help retain moisture without trapping humidity around the stems.
Lavender prefers slightly alkaline to neutral soil (pH 6.5–7.5). Acidic soils (pH below 6) can inhibit nutrient uptake, leading to yellowing leaves (chlorosis). Iron or magnesium deficiencies are common in acidic conditions, causing interveinal yellowing. Test your soil pH and amend it with lime if too acidic. Avoid heavy fertilizers, as lavender thrives in low-fertility soils. Excess nitrogen can also cause lush, weak growth prone to browning.
Fungal pathogens like Fusarium or Verticillium wilt can invade lavender, causing yellowing, browning, and wilting. These diseases block water transport in the plant. Root rot (from overwatering) often accompanies these symptoms. Bacterial leaf spot may also cause brown lesions. Remove affected foliage, improve air circulation, and avoid overhead watering. Fungicides may help in severe cases, but prevention through proper care is key.
Though lavender is pest-resistant, aphids, spider mites, or spittlebugs can occasionally attack. These pests suck sap, stressing the plant and causing yellow or brown stippling on leaves. Check for tiny insects or webbing under leaves. Blast pests off with water or use insecticidal soap. Avoid broad-spectrum pesticides, which harm beneficial pollinators attracted to lavender.
Lavender dislikes high humidity, which fosters fungal growth and leaf discoloration. In humid climates, ensure ample spacing for airflow. Winter wetness can also cause browning—protect plants with gravel mulch or raised beds. Frost damage may turn leaves brown; prune affected parts in spring. Conversely, intense heat without acclimation can scorch leaves, causing browning at the tips.
Older lavender stems naturally turn woody and may develop brown or yellow leaves as part of their lifecycle. Regular pruning (after flowering) encourages new growth and prevents legginess. Avoid cutting into old wood, as lavender may not regenerate from non-green stems. If the plant is over 5–10 years old, consider replacing it, as productivity declines with age.
Neglecting to prune lavender leads to woody, unproductive growth with sparse, discolored foliage. Prune annually, removing about one-third of the green growth in early spring or after blooming. Avoid cutting into bare stems, as this can stunt recovery. Proper pruning maintains shape, improves airflow, and prevents inner browning.
