MONO-POTASSIUM PHOSPHATE · 0-52-34
Monopotassium phosphate (MKP)
A fully water-soluble phosphorus-potassium fertilizer with no nitrogen and no chloride. Available as crystal, puffed and aerial grades, differing in dissolution speed and nozzle compatibility.

SPECIFICATION
Key figures
| P₂O₅-K₂O | 52-34 (86% combined) |
|---|---|
| Grades | Crystal / puffed / aerial |
| Water-insoluble content | ≤0.2% (premium grade) |
| Chloride | Nil |
| pH (1% solution) | 4.3–4.7, mildly acidic |
| Dissolution | Crystal slower; puffed and aerial fast |
| Packing | 1 / 5 / 25 kg |
Ranges are typical; the contract and the lot report govern.
WHY IT MATTERS
Why phosphorus and potassium decide fruit size
1. Two nutrients, two jobs
Phosphorus drives cell division, so it sets how many cells a fruit can have. Potassium drives sugar transport and osmotic regulation, so it sets how large and how sweet those cells become. Applied at fruit set, MKP supports both; applied after cell division is finished, it cannot add cells that were never formed.
2. Why MKP rather than potassium sulphate
MKP supplies phosphorus and potassium together, dissolves completely, contains no chloride and has a low salt index — so it can be sprayed at concentration without leaf burn. Potassium sulphate dissolves slowly and carries sulphur, which makes it unsuitable for high-concentration foliar work.
3. Crystal, puffed or aerial grade
Crystal is the cheapest form and suits root application. Puffed has lower bulk density and dissolves faster, shortening spray preparation. Aerial grade is milled and formulated for low-volume drone spraying so fine nozzles do not clog and coverage stays even.
4. Mild acidity helps compatibility
A pH of 4.3–4.7 keeps most tank mixes stable, though calcium and copper products still need a jar test before mixing.
DEFICIENCY
What phosphorus and potassium shortage costs
A deficiency is not a small yield loss; it accumulates from establishment.
- P shortage at fruit set: fewer cells per fruit — later potassium cannot compensate for size.
- K shortage at colouring: poor sugar transport, uneven colour, lower brix and shorter shelf life.
- Reduced stress tolerance: potassium regulates stomata; deficiency shows first as wilting under heat or drought.
- Spray risk: using non-aerial grade in a drone blocks nozzles and produces uneven coverage or local phytotoxicity.
Easily confused with
- Old leaves firstmobile nutrients: N, P, K, Mg
- New leaves firstimmobile: S, Fe, Zn, Cu
- Margin scorchK deficiency or salinity
- Uniform yellowing, normal shapecheck sulphur
FIELD DATA
Aerial application trial data
Trial block received our product; control block received an imported brand at the same grade. Same field, same management.
| Site | Crop | Trial (Suitinn) | Control (imported) | Difference |
|---|---|---|---|---|
| Fruit trial A | Fruit length / width | 71.6 / 73.2 mm | 60.7 / 60.2 mm | +18% / +21.6% |
| Fruit trial A | Fruit per plant | 23 | 15 | +53.3% |
| Fruit trial B | Fruit per plant | 102 | 89 | +14.61% |
| Root crop trial | Unit weight / yield | 228 g / 16.5 t·ha⁻¹ | 194 g / 14.8 t·ha⁻¹ | +17.53% / +11.49% |
Trials carried out in China by our partner plant; results vary with soil, climate and management.
APPLICATION
Rates and timing
| Crop | Stage | Rate | Method |
|---|---|---|---|
| Fruit trees (sizing / colouring) | Fruit set to colour break | 0.2–0.3% solution | Foliar, every 7–10 days, 2–3 sprays |
| Vegetables | Fruiting | 0.2% solution | Foliar or through fertigation |
| Drone application | Per spray window | Per spray plan | Aerial grade only; jar test before mixing |
| Root application | Fruit sizing | 45–75 kg/ha | Fertigation, avoid alkaline mixes |
Spray before 10 am or after 4 pm; high temperature concentrates the droplet and risks leaf burn.
FAQ
Common questions
Crystal or puffed?
For root application crystal is cheaper; for fast tank preparation puffed is quicker; for drone spraying only aerial grade should be used.
Can it be tank-mixed with pesticides?
Usually yes, but calcium and copper products can precipitate. Run a jar test: mix at the intended ratio, wait 30 minutes, check for cloudiness.
What concentration should I use?
0.2–0.3% for foliar sprays — 200–300 g per 100 litres. Use the lower figure in hot weather and on seedlings.
Why is aerial grade different?
Drones apply 15–30 litres per hectare with fine nozzles. Aerial grade dissolves faster and is milled to avoid nozzle blockage and uneven deposition.
Need this grade for your market?
Send the crop, the grade and the destination port. We reply within one working day.
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