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Arizona Sweet Orange with Black Spots: Watering and Fungus Issues

Newly Planted Citrus Shows Leaf Spots and Color Loss

Orange tree in Yuma, AZ watered daily for 15 days, then twice weekly for 40 minutes, with fertilizer spike. Black spots on leaves, some in leaf tissue.

Expert Feedback

Kathy says watering is excessive (recommends 3x/week for a month in FL, then weekly 3.5 inches). Fertilizer spikes are high in salt/chlorine; use slow-release. Likely fungal issue corrected by proper watering and fungicide or Atomic Grow. Keep ground bare under tree.

Follow-Up on Palms

For Mediterranean and Phoenix palms in 115–120°F heat, consult local Extension. Kathy uses horse manure for citrus.

Plant Diseases: Orange Tree Sudden Leaf Drop in Cool Weather: Temperature Fluctuation, Watering, or Scale—Cultural Fixes; Black Spots on Maple Leaves: Tar Spot Fungus—Rake Leaves, Reduce Inoculum, Tree Usually Fine; Blood Orange Leaf Curl: Insect Pest Diagnosis; Leaf Spots on Dwarf Pear: Need Photos and Pattern Details; Miniature Orange Tree Recovery: Water Stress and Sun Acclimation; Cedar-Apple Rust on Apple Trees: Identification and Management; Rust‑Colored Spots on Young Valencia Orange Leaves; Miniature Orange Tree Leaf Curl and No Flowers: Pot‑Bound or Pests?; Yellowing Leaves on a Young Arizona Sweet Orange Tree; Citrus Scab on Arizona Sweet Orange: Neem Oil for Fungal Lesions

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