3105 - Mineral or chemical fertilizers containing two or three of the fertilizing elements nitrogen, phosphorus and potassium; other fertilizers; goods of this chapter in tablets or similar forms or in packages of a gross weight not exceeding 10 kg:

This HTS category, 3105, encompasses a broad range of mineral or chemical fertilizers designed to enrich soil with essential plant nutrients. Specifically, it covers fertilizers that contain combinations of nitrogen (N), phosphorus (P), and potassium (K), which are the primary macronutrients for plant growth. This includes compound fertilizers with two or all three of these elements, as well as specially prepared forms like tablets or packages weighing up to 10 kg.

Distinguishing this category from its siblings within the broader HTS system is crucial. While other chapters might cover organic materials or raw minerals, Chapter 31, and specifically heading 3105, is dedicated to *processed* fertilizers. Unlike heading 3102 (mineral or chemical fertilizers, nitrogenous) or heading 3103 (mineral or chemical fertilizers, phosphatic), heading 3105 focuses on combinations and multi-nutrient formulations, reflecting more complex fertilizer products.

The subcategories within 3105 provide a granular breakdown of these compound fertilizers. They differentiate based on the specific elements present (nitrogen and phosphorus, or phosphorus and potassium) and the chemical composition, such as diammonium hydrogenorthophosphate and ammonium dihydrogenorthophosphate. This detailed classification allows for precise identification of diverse fertilizer types, from complex NPK blends to specialized phosphate derivatives, ensuring accurate trade data and customs processing.