Potassium fertilizers
SOP Water Soluble — Chloride-Free Potassium & Sulphur for Fertigation
FOB Black Sea / MENA · CFR/CIF worldwide on request
Indicative price
USD 558–680 / MT
Indicative range, firm quote on request
Key parameters
Full product details
Product overview
Water-soluble sulphate of potash delivers 50% K2O and 17% S in a micronized crystalline form that dissolves completely at fertigation concentrations. Unlike granular SOP, the soluble grade is milled to tight particle-size limits so stock solutions remain clear and drip emitters stay free of sediment. Chloride stays below 1.5%, protecting tobacco, potato, grape, citrus and greenhouse crops that accumulate chloride to toxic levels under continuous fertigation.
Primary buyers include protected-culture growers running A/B fertigation systems in Spain, Morocco and the Gulf, export-oriented berry and vegetable producers in Chile and Peru, and liquid-fertilizer blenders formulating chloride-free potassium sources. The grade suits pivot and micro-sprinkler injection as well as subsurface drip on orchard replant programmes where soil salinity limits MOP use.
Full specification
- FOB
- CFR
- CIF
- Fertigation
- Greenhouse
- Orchards
Loading ports & logistics
Soluble SOP ships from Black Sea load ports (Novorossiysk, Constanta) and selected MENA terminals. Bagged parcels of 300–3,000 MT load into 20 ft and 40 ft containers; larger programmes above 1,000 MT can move on breakbulk or geared bulkers with palletized 25 kg bags. Loading rates 200–400 MT/day for container stuffing, faster on dedicated bagging lines. CFR/CIF covers ocean freight to nominated discharge — common destinations include Valencia, Casablanca, Jeddah, Mumbai and Colombo. Lead time 10–20 days after contract signing and payment confirmation.
Packaging & documentation
Standard export pack: 25 kg PE-lined PP woven bags, palletized and stretch-wrapped for container loading. One-tonne FIBC big bags available for inland distribution hubs. Each lot ships with mill certificate of analysis (K2O, S, Cl, moisture, water insolubles), commercial invoice, packing list and full bill of lading set. SGS or equivalent pre-shipment inspection on request. HS classification 3104.30 — potassium sulphate.
FAQ
When should growers choose water-soluble SOP over granular SOP?
Water-soluble SOP is the right grade for drip, pivot and sprinkler fertigation where nutrients must dissolve completely before reaching emitters. Granular SOP suits broadcast and bed application on field crops; the soluble grade commands a premium but eliminates sediment in stock tanks and clogged drip lines.
What mixing conditions ensure full dissolution of soluble SOP?
Use irrigation water above 20°C and allow 15–30 minutes of agitation in the stock tank. At 10°C dissolution slows noticeably — pre-warm concentrate tanks in greenhouse operations or split dosing across two irrigation cycles on cold mornings.
Can water-soluble SOP replace potassium nitrate in fertigation programmes?
SOP supplies potassium and sulphur without nitrate, making it ideal during fruit ripening when excess nitrogen delays sugar accumulation. Programmes that need both nitrate and potash should alternate KNO₃ and soluble SOP by growth stage rather than substituting one for the other year-round.