Why Are My Jalapenos Dropping Leaves?

Improper Watering

• Among the most common causes of leaf drop in jalapeno plants is improper watering. Too little water starves and dehydrates the plant, causing it to drop leaves and fruit in an effort to stay alive. Water jalapeno plants deeply but infrequently, allowing the top 1 inch of soil to dry out slightly between waterings to discourage pests and disease. Run water at the base of the plants until the top 3 inches of soil feel moist. In hot climates, spread a 2-inch layer of mulch between the jalapeno plants to reduce moisture loss and decrease the need for frequent watering. Avoid splashing water onto the leaves because it encourages pests and pathogens.

Aphid Damage

• Leaf drop is one symptom of an aphid infestation in jalapeno plants, as well as yellowing of the leaves and a sticky, honeydew liquid on the stems and leaves. Only severe infestations cause leaf drop, so you'll need to treat this type of problem with an aggressive treatment with insecticidal oil. Spray the plant liberally with a ready-to-use neem oil to smother the aphids and eggs. Dissuade further infestations by clearing away old vegetation and by limiting the use of nitrogen-rich fertilizers. Monitor the plants closely for the first signs of aphids so the problem can be treated before leaf drop starts.

Bacterial Spot

• Bacterial spot is caused by the bacterium Xanthomonas campestris, which strikes jalapeno pepper plants during cool, wet weather. An early symptom of bacterial spot is the appearance of round, weeping spots on the leaves. The leaves begin to drop as the infection progresses, at which point it may have spread into the stems. Prevention is the best way to deal with bacterial spot. Plant only clean, disease-free seeds in sterilized soil and avoid growing peppers in the same bed for more than one year in a row because the bacteria persists in the soil. At the first sign of infection, spray the jalapeno plants with ready-to-use copper fungicide once a week until the problem subsides.

Age-Related Leaf Loss

• Jalapeno plants drop older foliage as they age, redirecting the energy toward new leaves. Age-related leaf loss differs from disease-related foliage loss in that only the bottom leaves fall while the younger leaves at the top of the plant remain unaffected. Nothing can be done to prevent or correct the loss of older foliage, although you should remove fallen leaves from around the base of the plant because it provides a habitat for pests and diseases.