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Black-Eyed Susan Fungal Disease: Prevention Only

Black, dry leaves on Rudbeckia = incurable fungal disease. Remove infected plants. Next year: preventive copper fungicide (Soap Shield) every 14 days from bud stage. 3 tbsp/gal. Organic, effective.

Program

Start spraying at first buds.
Continue 14-day intervals.
Soap Shield adheres best (fatty acid carrier).
Also protects zinnias, vegetables.

Prevention works; cure doesn't exist.

Growing Vegetables: Black-Eyed Susan Leaf Spots: Fungal Diseases, Cultural Control; Climbing Black-Eyed Susan Yellow Spots: Bacterial Leaf Spot and Bloom Boost; Rescuing Black-Eyed Susans from Root Rot in Wet Conditions; Rudbeckia (Black-Eyed Susan) Foliage Decline: Multiple Culprits; Weak, Late-Blooming Black-Eyed Susans: Soil, Sun, and Variety Issues; Black‑Eyed Susans Fail to Emerge in Ottawa: Likely Dead; Potted Black-Eyed Susan Drying Out: Root Shock and Overwatering; Black-Eyed Susan (Rudbeckia): Growing America's Favorite Wildflower; Black-Eyed Susan 'Goldsturm': Award-Winning Perennial; Black-Eyed Susan 'Goldsturm' – Award-Winning Perennial for Borders and Cut Flowers

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