Engrais hydrosoluble vs granulé : lequel choisir pour la fertirrigation ?
Les producteurs demandent souvent s'il faut utiliser un engrais hydrosoluble ou granulé en fertirrigation. Comparaison pratique pour décider.
Many growers moving to drip irrigation or fertigation ask the same question: should I buy water-soluble fertilizer or stick with granular products? The answer depends on your irrigation system, crop and target timing of nutrient delivery.
The key difference: dissolution
Water-soluble fertilizers are designed to dissolve completely and quickly in water, leaving no residue to clog emitters or filters. Granular fertilizers release nutrients more slowly and depend on soil moisture; they are better suited to broadcasting and pre-plant incorporation than to injection through drip lines.
When water-soluble is the right choice
- Drip irrigation and fertigation systems, where a clean, residue-free solution is essential.
- High-value fruit, vegetable and greenhouse crops that need precise, split nutrient delivery.
- Foliar feeding and drone (UAV) spraying, which require a completely soluble, low-residue product.
When granular may be enough
- Broadcast or banding applications before planting on field crops.
- Slow-release or controlled-release programs where labor for frequent applications is limited.
- Systems without injection equipment, where nutrients are applied by hand or mechanical spreader.
Fertigation-specific products
For fertigation, choose an analysis that matches the crop stage: a high-phosphorus product such as MKP 0-52-34 supports root development and flowering, while nitrogen and potassium sources drive vegetative growth and fruit fill.
FAQ
- Can I put granular fertilizer in a fertigation tank? Generally no — partially soluble granules can clog injectors and drip emitters; use a fully water-soluble grade.
- Is water-soluble fertilizer more expensive? Per kilogram it can cost more, but it is applied in precise, lower doses and reduces waste, so the effective cost is often comparable.
- What is the best fertilizer for drip irrigation? A fully water-soluble NPK or PK product matched to the crop stage, such as MKP for flowering and fruiting.
- Does water-soluble fertilizer leave residue? A high-purity product dissolves completely and leaves negligible water-insoluble residue.