Brown spots on jalapeno peppers are a common issue. This guide explores their causes and offers practical strategies for prevention and treatment.
Understanding Why Jalapenos Develop Brown Spots
Brown spots on jalapeno peppers can arise from several factors, ranging from environmental stresses to pest activity. Recognizing the specific characteristics of these spots can help pinpoint the underlying issue.
Sunscald
Sunscald occurs when pepper fruits are exposed to intense sunlight. This damage manifests as bleached, white, or pale areas on the fruit’s skin, which later turn brown and become papery or leathery. It is common when plants have insufficient foliage to shade developing peppers.
Blossom End Rot
Blossom end rot (BER) is a physiological disorder, not a disease. It presents as dark, sunken, and leathery spots on the blossom end of the pepper fruit. This condition results from a localized calcium deficiency, often linked to inconsistent soil moisture. Rapid plant growth or excessive nitrogen fertilization can also contribute to BER.
Fungal and Bacterial Issues
Fungal and bacterial infections cause brown spots. Anthracnose, a common fungal disease, appears as sunken, water-soaked spots on the fruit, which can enlarge and develop concentric rings, often with salmon-colored spores. Bacterial spot, caused by Xanthomonas species, leads to raised, rough, wart-like brown spots on the fruit, sometimes starting as small spots on leaves.
Insect Damage
Insect pests can cause physical damage. The pepper weevil lays eggs in small fruit and flowers, creating puncture marks that result in oviposition warts. Larvae feed internally, and adult feeding can cause flowers and young fruit to abort or deform. Stink bugs also cause cosmetic damage, leaving scarred or discolored spots where they feed.
Identifying the Specific Cause of Brown Spots
Distinguishing the cause of brown spots requires observing their appearance, location, and any accompanying plant symptoms. Sunscald appears on sun-exposed fruit sides, starting pale before turning brown and papery. Blossom end rot consistently forms at the fruit’s bottom (blossom end) as a dark, sunken, leathery patch, unrelated to pathogens.
Fungal diseases like anthracnose create distinct, often circular, sunken lesions with visible spore masses and concentric rings, appearing anywhere on the fruit. Bacterial spot results in small, raised, scabby brown spots on the fruit, sometimes with leaf yellowing. Insect damage leaves specific marks like puncture wounds, feeding scars, or deformities, and may show internal damage.
Effective Strategies for Prevention and Treatment
Preventing brown spots involves good gardening practices. Consistent watering prevents blossom end rot by ensuring steady calcium uptake. Mulching retains soil moisture, benefiting both sunscald and blossom end rot prevention.
For sunscald, provide shade during hot periods using shade cloth or companion plants. Encourage dense foliage growth through balanced fertilization to shield fruit. To address blossom end rot, ensure consistent moisture and adequate soil calcium by maintaining a soil pH around 6.5, avoiding excessive nitrogen. Foliar calcium sprays are generally ineffective.
Managing fungal and bacterial issues requires good sanitation, like removing infected plant debris and avoiding overhead watering. Crop rotation prevents pathogen buildup. For bacterial spot, use disease-free seeds and consider copper-based sprays. For insect damage, regular scouting and cultural controls like removing fallen fruit reduce pest populations. Targeted insecticides may be necessary for severe infestations.
Harvesting and Consuming Brown Spotted Jalapenos
When jalapeno peppers develop brown spots, their edibility depends on the cause and severity. Peppers with minor sunscald or blossom end rot are generally safe to eat; simply cut away the affected parts. However, if spots are from widespread fungal or bacterial diseases, especially if the fruit is soft, mushy, or moldy, discard them to avoid health risks. For superficial insect damage, peppers may be edible after removing the affected area, provided no secondary rot or extensive internal damage exists.