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Greenhouse Tomato Fungus: Copper Fungicide Solution

Black spores on tomato leaves/stems in humid greenhouse = fungal disease. Best treatment: copper fungicide (Soap Shield—fatty acids boost adhesion, no sulfur needed). Remove worst leaves, improve airflow, water at base only.

Action Plan

Spray Soap Shield per label.
Vent greenhouse aggressively.
Space plants, stake, mulch.
Water soil only, morning only.

Other crops unaffected—tomatoes are the target.

Growing Vegetables: Heirloom Tomato Lower Leaf Yellowing: Septoria vs. Bacterial Spot in Organic System; Shriveled, Brown Tomato Leaves: Root Stress, Not Disease; Nepenthes Red/Black Leaves in Terrarium: Soil Breakdown and Overwatering; Black Leaves on Houseplants After a Day Outdoors: Sun and Heat Damage; Tomato Leaf Curl & Tiny Grub: Don't Panic, It's Minor; Yellow Leaves on Container Tomatoes: Watering and Fertilizing Fixes; Twisted & Purplish Tomato Leaves: Overwatering or Overfertilizing; Container Cucumber & Tomato: Skip Eggshells/Coffee, Use Real Fertilizer; Black Pepper Leaves After Soap Spray: Acid Burn Recovery; Sun Scald on Newly Transplanted Tomatoes: Recovery Plan

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