NPK fertilizers are sold by three numbers, but choosing between 19-19-19, 13-40-13 or 12-61-0 is where many buyers and growers get stuck. This guide decodes the numbers, explains what each popular water-soluble grade is designed to do, and shows how to build a simple stage-by-stage programme.
Key takeaways
- The three numbers are the percentage of nitrogen (N), phosphate (P₂O₅) and potash (K₂O).
- High-phosphorus grades (12-61-0, 14-48-0, 13-40-13) support roots and flowering; balanced grades (19-19-19) drive vegetative growth.
- “+ TE” means the grade includes trace elements for broader nutrition.
- Customised NPK ratios can be produced to match your programme or local registration.
What do the NPK numbers mean?
Every NPK grade lists three percentages in a fixed order: N (nitrogen), P₂O₅ (phosphate) and K₂O (potash). A 25 kg bag of NPK 19-19-19 therefore contains 19% of each — about 4.75 kg of N, 4.75 kg of P₂O₅ and 4.75 kg of K₂O.
- Nitrogen drives leaf and shoot growth and gives crops their green colour.
- Phosphorus fuels root development, energy transfer, flowering and seed set.
- Potassium regulates water use and moves sugars into fruit, improving size, colour, taste and shelf life.
The popular water-soluble NPK grades
MAP 12-61-0 (Mono Ammonium Phosphate)
One of the most concentrated sources of soluble phosphorus. MAP 12-61-0 is widely used in the early weeks after sowing or transplanting to build a strong root system, and again before flowering. Its ammonium nitrogen also has a mild acidifying effect, which can help in alkaline water.
NPK 14-48-0 + TE
A high-phosphorus starter fortified with trace elements. It is designed for fast root establishment and healthy early growth, and is a good choice for nursery stock and newly transplanted vegetables.
NPK 28-28-0
High in both nitrogen and phosphorus, this grade pushes rapid leaf and shoot growth while continuing to support roots. It suits leafy vegetables and the early vegetative phase of fruiting crops.
NPK 19-19-19
The classic balanced grade. Equal N, P and K make 19-19-19 a dependable all-rounder for the vegetative stage and for general fertigation of field and greenhouse crops. Our value grade is popular with distributors who need a competitively priced, high-volume product.
NPK 13-40-13
A phosphorus-rich “bloom booster” with balanced nitrogen and potash. Growers apply 13-40-13 before and during flower initiation to encourage more flowers and better fruit set.
NPK 11-42-11 + TE
Similar in purpose to 13-40-13, with added trace elements to correct minor micronutrient gaps while supporting both root strength and flowering.
Choosing a grade by crop stage
| Crop stage | Nutrient focus | Suggested grades |
|---|---|---|
| Establishment & rooting | High phosphorus | 14-48-0 + TE, MAP 12-61-0 |
| Vegetative growth | Nitrogen + balance | 19-19-19, 28-28-0 |
| Pre-flowering & flowering | Phosphorus + potash | 13-40-13, 11-42-11 + TE |
| Fruit fill & maturity | High potash | 13-0-45, SOP 0-0-50, potassium schoenite |
Indicative guidance only. Rates and timing depend on crop, soil, water quality and local agronomic advice.
For the fruit-fill stage, see our comparison of SOP 0-0-50, potassium nitrate and potassium schoenite.
What does “+ TE” mean?
TE stands for trace elements — micronutrients such as zinc, iron, manganese, copper, boron and molybdenum, needed in small amounts but essential for enzyme function, chlorophyll and flowering. Grades marked + TE add these to the NPK base so a single product covers more of the crop’s needs. Where deficiencies are severe, a dedicated liquid micronutrient mix may still be needed.
Customised NPK for distributors and brands
Many importers need a ratio that matches local crop programmes or the grades already registered in their country. Mitra Eco Exports supplies customised NPK in powder or liquid form, packed in neutral or private-label bags carrying your brand. Share the grade, quantity and destination port and we will return a tailored quotation.
Need a quotation?
Tell us the product, quantity and destination port. Our export desk replies within 24 hours with pricing, specifications and sample availability.
Frequently asked questions
What is NPK 19-19-19 used for?
NPK 19-19-19 is a balanced water-soluble fertilizer used mainly during the vegetative stage and for general fertigation, supplying equal nitrogen, phosphorus and potash.
Which is better for flowering, 13-40-13 or 19-19-19?
13-40-13 is the usual choice before and during flowering because of its high phosphorus content. 19-19-19 is better suited to steady vegetative growth.
Is MAP 12-61-0 water soluble?
Yes. Water-soluble MAP 12-61-0 dissolves fully and is suitable for drip irrigation and foliar spray.
Can you export NPK fertilizers in our own brand bags?
Yes. We offer private-label and neutral packaging for all our NPK grades.
This guide is for general information. Application rates and product choice depend on crop, soil, water quality and local regulations; please consult a qualified agronomist and check registration requirements in your country.