Water-soluble / specialty fertilizers
Magnesium Sulphate (Kieserite) — Soluble Mg & S for Fertigation & Blending
FOB Black Sea / MENA · CFR/CIF worldwide on request
Indicative price
USD 107–130 / MT
Indicative range, firm quote on request
Key parameters
Full product details
Product overview
Kieserite (magnesium sulphate monohydrate, MgSO₄·H₂O) is a naturally derived mineral fertilizer supplying 27% MgO and 21% S in a low-chloride, water-soluble form. Magnesium drives chlorophyll synthesis and enzyme activation; sulphur supports protein formation and oil content in oilseed crops. On sandy, heavily leached or high-potassium soils, kieserite corrects interveinal chlorosis on older leaves without adding nitrogen that could delay fruit maturity.
Primary buyers include NPK blending plants fortifying compound granules with Mg and S, greenhouse cooperatives running magnesium correction through drip lines, potato and tobacco growers avoiding chloride-based magnesium sources, and distributors serving Central European, Black Sea and MENA markets where kieserite competes favourably on delivered MgO cost versus imported epsom salt.
Full specification
- FOB
- CFR
- CIF
- Fertigation
- Blending
- Field crops
Loading ports & logistics
Kieserite ships from Black Sea load ports (Novorossiysk, Constanta) and selected MENA bagging terminals. Bagged parcels of 500–5,000 MT load into 20 ft and 40 ft containers; larger programmes above 2,000 MT can move on breakbulk with palletized 25 kg or 50 kg bags. Bulk kieserite in hopper trucks is available for inland EU destinations on request. Loading rates 250–450 MT/day depending on bagging line. CFR/CIF covers ocean freight to nominated discharge — common routes include Constanta–Alexandria, Novorossiysk–Mumbai and Baltic–Casablanca. Lead time 10–22 days after contract signing and payment confirmation.
Packaging & documentation
Standard export pack: 25 kg or 50 kg PE-lined PP woven bags, palletized and stretch-wrapped for container loading. One-tonne FIBC big bags available for blending plants and inland distribution hubs. Each lot ships with mill certificate of analysis (MgO, S, Cl, moisture, water solubility), commercial invoice, packing list and full bill of lading set. SGS or equivalent pre-shipment inspection on request. HS classification 2833.21 — magnesium sulphate.
FAQ
When should buyers choose kieserite over epsom salt (magnesium sulphate heptahydrate)?
Kieserite (monohydrate) carries 27% MgO in a stable granular form with lower moisture and better flowability for bulk blending and mechanical spreading. Epsom salt heptahydrate dissolves faster in cold water and suits small-pack horticulture, but its higher water content raises freight cost per unit of MgO on ocean routes.
Can kieserite be injected through drip fertigation systems?
Yes, when milled to soluble grade or pre-dissolved in a stock tank with agitation. Allow 20–40 minutes dissolution at irrigation water above 18°C. Use 120-mesh filtration on the injection line and avoid mixing concentrated kieserite solution with phosphate concentrates in the same tank.
How does magnesium sulphate compare to magnesium nitrate for crop correction?
Magnesium sulphate supplies Mg and S without nitrogen — preferred when nitrate levels are already high or during fruit ripening. Magnesium nitrate adds 11% N alongside MgO and suits hydroponic systems where both nutrients are deficient simultaneously.
Related products
- Magnesium Nitrate 11-15 — crystalline Mg + N for hydroponics
- Calcium Nitrate 15.5-26 — soluble Ca + N for greenhouse fertigation
- Ammonium Sulphate 21-24 — granular N + S for sulphur-deficient soils