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Tomatoes Turning Black or Rusty: Causes and Help

Tomatoes developing black or rust-colored areas may be affected by a fungal disease or a reaction to fertilizer or soil contaminants. Remote diagnosis is difficult.

Next Steps

Consult a local garden center, nursery, or state extension service.
Ask if similar cases have been reported in your area.
Bring a sample or clear photos for accurate identification.

Local experts can provide region-specific diagnosis and treatment options.

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