Home / Products / Sulphate-based Compound NPK 18-18-18

Sulphate-based Compound NPK 18-18-18

A balanced compound for chloride-sensitive and quality crops. Potassium comes from sulphate of potash, so the granule carries no chloride load and supplies sulphur.

18-18-18N-P-K ≥85%water-soluble P 1×20'GPminimum order
Get a Quote Request TDS / COA
Sulphate-based Compound NPK 18-18-18

SPECIFICATION

Technical data

N-P₂O₅-K₂O18-18-18 (54% total)
Water-soluble P≥85% of available P₂O₅
Potassium sourcePotassium sulphate (SOP)
ChlorideLow, ≤3%
Sulphur8–10% as S
Moisture≤1.5%
Granule size2–4 mm
Granule strength≥25 N, suitable for mechanical spreading
Packing25 kg / 50 kg / 1,000 kg

Typical values. The contract and the lot COA govern; ranges vary by formulation and raw material lot.

What it is

A three-nutrient compound granulated from sulphate of potash, monoammonium phosphate and ammonium sulphate. Because the potassium source is sulphate rather than chloride, the product can be used on crops that react badly to chloride, and it supplies 8–10% sulphur, a nutrient that is often short in soils that no longer receive single superphosphate.

How it works

Phosphorus in this grade is 85% water-soluble, so a larger share is available in the season of application rather than being fixed in the soil. Nitrogen is present in ammonium form, which is taken up steadily rather than in a single flush. Sulphur drives protein and oil synthesis, which is why tobacco, oilseed and allium crops respond to it visibly.

APPLICATION

Crops and rates

Convert kg/ha to kg/acre by dividing by 2.47. Local registration and recommendations take priority.

CropStageRateNote
TobaccoBasal + side-dress300–450 kg/haChloride affects leaf burn quality
PotatoBasal500–800 kg/haSulphate supports starch accumulation
Citrus / fruit treesPre-flush and sizing0.5–1.5 kg/treeAvoids chloride accumulation
CucurbitsBasal at transplanting450–700 kg/haYoung plants are chloride-sensitive
Garlic / onionBasal + top-dress400–600 kg/haSulphur drives pungency and bulb size

ADVANTAGES

What you get

  • 85% water-soluble P — the share that works in the year you apply it
  • Sulphate of potash, not chloride — safe on tobacco, potato and citrus
  • 8–10% sulphur included, not invoiced separately
  • Granule strength ≥25 N — survives mechanical spreading

Before you apply

  • Do not mix with lime or alkaline materials at application.
  • On sandy soils, split the nitrogen into two applications.
  • Store in a dry, ventilated place; reseal opened bags.

FAQ

Common questions

Is it suitable for tobacco?

Yes. Chloride affects leaf burn quality, so tobacco is the crop where the sulphate premium pays back most reliably.

How is it different from a chloride grade?

The potassium source. Sulphate of potash costs more but carries no chloride and adds sulphur. Use it for sensitive crops, not for rice or corn.

Can it be used in drip irrigation?

Broadcast or band application is the intended use. For drip, use the water-soluble 17-17-17 grade instead.

What is the minimum order?

One 20'GP container, 25–27 tonnes depending on bag size. Mixed grades are possible.

Ask for the specification and a COA sample

Send the volume and destination port, and we reply within one working day.

Get a Quote