Iron sulphate

Iron sulphate (ferrous sulphate) is a widely used chemical compound in agriculture, primarily serving as a fungicide, bactericide, and a source of essential iron for plants. It typically appears as blue-green crystals and is highly soluble in water. In terms of chemical classification, it is the iron salt of sulfuric acid, known for its strong oxidizing and desiccant properties in certain applications.

The mechanism of action involves creating a toxic environment for fungal spores and bacterial cells through the release of iron ions. When applied as a foliar spray or a trunk wash, it effectively dries out the surface of pathogens, preventing their germination and spread. Furthermore, it acts as an effective herbicide against mosses and liverworts in lawns, causing them to blacken and die without harming the surrounding grasses if applied correctly.

It is commonly applied to a variety of crops, including pome fruits, stone fruits, and grapevines. It is primarily used to combat scab, powdery mildew, anthracnose, and various types of wood rot. In addition to its fungicidal properties, it is highly valued by gardeners for treating chlorosis in plants, a condition caused by iron deficiency, which leads to yellowing of leaves and stunted growth.

Effective application requires precision, especially concerning concentration. During the dormant season, higher concentrations are used to eradicate overwintering spores on bark and twigs. Conversely, during the growing season, extreme caution is necessary; high concentrations can cause severe leaf scorch, so only very dilute solutions should be used if at all during active vegetation.

• Always use non-metallic containers for mixing to prevent corrosive chemical reactions.
• Apply during calm, dry weather to ensure uniform coverage and efficacy.
• Avoid mixing with incompatible alkaline substances like lime, which can neutralize its acidity.
• Wear protective equipment, as the product can cause irritation to skin and respiratory tracts.