Chemical & Physicochemical Properties Copper hydroxide [Cu(OH)₂] is a high-purity inorganic copper compound formulated to deliver maximum biological activity with controlled phytotoxicity risk. Its low intrinsic solubility in water ensures that copper ions are not released instantaneously, but rather liberated gradually upon hydration and deposition on plant surfaces.
The formulation is engineered with a controlled particle size distribution, which is critical for: Uniform leaf surface coverage Optimized adherence to waxy cuticles Controlled Cu²⁺ ion release kinetics Reduced risk of localized copper accumulation The wettable powder formulation allows rapid dispersion in spray tanks while maintaining physical stability and suspension uniformity during application.
Copper hydroxide 770 g/kg
WP (Wettable powder)
FRAC M01 (Multi-site contact)
Foliar spray
2.0–3.0 kg per hectare
12 hours
Copper hydroxide releases copper ions on contact with moisture, and those ions disable a wide range of enzymes and proteins inside any fungal or bacterial cell they touch, rather than hitting one specific target. That's why it's effective as a preventive barrier against spores landing on the leaf, but has no effect once a pathogen is already established inside plant tissue.
It needs to be on the surface before infection happens, which means reapplication after heavy rain or new growth is what keeps protection continuous through the season.
Recommended rate: 2.0–3.0 kg per hectare
| Crop | Target | Timing | Max |
|---|---|---|---|
| Dry beans | Bacterial leaf spot, Downy mildew & Rusts | Preventive | 3 |
| Irish potato | Bacterial leaf spot, Downy mildew & Rusts | Preventive | 3 |
Because copper disrupts so many targets in the fungal or bacterial cell at once, genuine resistance to it is rare, one of the lowest-risk options in the whole range, and it doesn't need the tight rotation schedule a single-site fungicide does.
The trade-off is timing, since it only works as prevention, good coverage ahead of wet weather matters far more than the product choice once bacterial leaf spot or downy mildew is already visible.
Copper can be phytotoxic in hot, slow-drying conditions, avoid spraying during the heat of the day and allow adequate drying time before rain or irrigation follows. It's also incompatible with acidic tank-mix partners, check compatibility before combining with anything else in the tank.
Wear chemical-resistant gloves and eye protection when handling, avoid inhaling dust when mixing this wettable powder. Store in the original container away from direct sunlight, children, food, and livestock.
Registered for use on labelled crops across East African markets, under the relevant national regulatory authority. Always read and follow the approved product label before use.
