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Treating Soilborne Fungus Killing Pelargoniums and Other Plants

Rapid stem browning spreading to roots across multiple species = soilborne fungus. Hard to cure. Spray copper-based fungicide (Soap-Shield from Gardens Alive). But first, take a 6" stem section and 8 oz soil sample to a nursery for testing. If soil is infected, solarize with 3-mil black plastic for several months before replanting.

Act fast — this spreads quickly in wet conditions.

Annuals: Troubleshooting Yellowing Yew After Transplant: Root Rot vs. Environmental Stress; Understanding Soil pH: What It Is, Ideal Levels, and How to Adjust It; Yard-Wide Stunted Growth: Soil Compaction, Nematodes, and Testing; White Root Threads: Beneficial Mycorrhizal Fungi, Not Disease; Dogwood Leaf Scorch in Sandy Soil: Environmental Stress, Not Fungus; Root Rot in Garden Beds: Diagnosing and Treating Soil-Borne Fungal Disease; Diagnosing and Treating Pale Foliage on Garden Plants; Soil Solarization: Eliminating Persistent Impatiens Diseases; Zucchini Blossom-End Rot: Soil Fungus Management and Crop Rotation; Diagnosing Root Rot, Nematodes, and Soil Disease in a New Garden

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