Banrot Fungicide for Orchids: Correct Usage as a Drench

Banrot (a wettable powder fungicide) is effective against many orchid fungi but not bacteria. The label rate of 2 tsp/gallon is below the recommended orchid rate. Here's the correct protocol from the American Orchid Society.

AOS-Recommended Banrot Protocol

• Rate: 1 tablespoon (3 tsp) per gallon water
• Method: Drench (soak pot/roots), NOT foliar spray
• Safety: Chemical-resistant gloves required
• Prep: Remove all infected tissue (roots, leaves) first
• Process: Unpot → drench in Banrot solution → repot in fresh media

Key Usage Notes

• Effective on: Cattleyas, Phalaenopsis, most orchids
• Ineffective against: Bacterial infections
• Not recommended as preventative by many growers
• Use for active fungal root/crown rot

Application Steps

1. Diagnose fungal issue (mushy roots, black crown spots)
2. Unpot, clean roots, remove all dead tissue
3. Mix Banrot at 1 Tbsp/gallon
4. Submerge root zone 15-30 minutes
5. Drain, repot in fresh, pre-moistened bark
6. Withhold water 3-5 days post-treatment

Alternatives

For routine prevention: cinnamon on cuts, good culture. For treatment: thiophanate-methyl (Cleary's 3336) or copper-based fungicides also effective.

Follow AOS rates, not supplier's generic rates. Drench application targets root zone fungi where they live.