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Citrus Fungus on Mexican Key Lime: Prune and Organic Spray

Orange powdery circles on bark with branch dieback on a 3-year-old Mexican key lime indicate a spreading fungal disease. The Extension office advised pruning the dead branch, but the fungus is already on healthy wood.

Integrated Approach

Remove the dead branch; dispose off-site.
Spray Atomic Grow on all foliage, trunk, and soil every 7-10 days.
Drench root zone monthly (20 tsp/5 gal).
Monitor for new lesions; treat promptly.

Atomic Grow is organic, safe for edibles, and strengthens the tree's natural defenses against citrus pathogens.

Plant Diseases: Key Lime Scale and Greening: Organic Approach with Atomic Grow; Key Lime Fruit Drop: Water Consistency and Pollination Boost; Key Lime Leaf Drop in the Florida Keys: Water, Wind, or Fungus?; Orange Circles on Key Lime Bark: Fungal Treatment with Atomic Grow; Key Lime Seasonal Leaf Drop and Leafminer: Normal Cycle and Organic Management; Key Lime and Ficus Hedge in Key Largo: Water, Leaf Miner, and Cuban Laurel Thrips; Key Lime Tree Not Fruiting: Causes and Solutions; Outdoor Pests on a Mexican Lime Tree; How to Plant a Dwarf Mexican Key Lime Tree; Key Lime (Citrus aurantifolia): The Classic Pie Citrus

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