Haifa's fertilization & fertigation recommendation for growing onions with Haifa fertilizers, to achieve optimal plant nutrition and excellent yield.
What is the best onion fertilizer?
Onions require a high source of nitrogen which is applied in the Planting and establishment stage and later on in the Development stage.
Situation A
Growing medium: Open field.
Soil type: Light.
Plant population: 200,000-400,000 Plants/Ha.
Expected yield: 40-60 T/Ha (85% moisture).
| N | P2O5 | K2O |
|---|---|---|
| ---------------- Kg/Ha ----------------- | ||
| 100-200 | 100-200 | 200-300 |
Base dressing
| Nutrient demand | Recommended fertilizers | |||||
|---|---|---|---|---|---|---|
| N | P2O5 | K2O | MgO | Multi-K | SSP | Magnisal |
| -------------- Kg/Ha -------------- | -------------- Kg/Ha -------------- | |||||
| 37 | 120 | 90 | 16 | 200 | 650 | 100 |
Due to shallow root system the fertilizers should be banded 8-10 cm below the seed row.
Fertigation
| Weeks after transplanting | Nutrient requirements | Recommended fertilizers | |||||
|---|---|---|---|---|---|---|---|
| N | P2O5 | K2O | Ca | Multi-K | AN | CN | |
| -------------- Kg/Ha -------------- | -------------- Kg/Ha -------------- | ||||||
| 2-6 | 14 | 0.9 | 40 | 4.5 | |||
| 8-12 | 6.5 | 23 | 50 | ||||
High nutrient availability is required during the bulbification.
AN = Ammonium nitrate (34% Nitrogen)
Multi-K = Potassium nitrate (13-0-46)
SSP = Single Superphosphate (19% P2O5)
Magnisal = Magnesium nitrate ( 10.8-0-0-+15.7MgO)
Situation B
Growing medium: Open field.
Soil type: Light to medium.
Plant population: 800,000-1,000,000 Plants/Ha.
Expected yield: 65-70 MT/Ha (85% moisture).
Recommended average rates of nutrients for onions
| N | P2O5 | K2O |
|---|---|---|
| ---------------- Kg/Ha ----------------- | ||
| 170-200 | 200-300 | 400-500 |
Base dressing
| Nutrient demand | Recommended fertilizers | |||||
|---|---|---|---|---|---|---|
| N | P2O5 | K2O | MgO | Multi-K | SSP | Magnisal |
| -------------- Kg/Ha -------------- | -------------- Kg/Ha -------------- | |||||
| 85 | 270 | 300 | 37 | 600 | 1400 | 230 |
Multi-K - Potassium nitrate (13% N and 46% K2O).
SSP - Single Superphosphate (19% P2O5).
Side-Dressing
| N | K2O | Multi-K | Ammonium Nitrate | Calcium nitrate | |
|---|---|---|---|---|---|
| Developmental stage | (Kg/Ha) | (Kg/Ha) | (Kg/Ha) | (Kg/Ha) | (Kg/Ha) |
| 2 weeks after transplanting | 30 | 70 | 150 | 0 | 0 |
| Bulb filling | 60 | 70 | 150 | 20 | 150 |
Note: It is recommended not to apply nitrogen after the bulb is 2/3 of its expected final size.
Multi-K - Potassium nitrate (13% N and 46% K2O).
Calcium nitrate (15.5% N and 20% Ca).
For more information on plant nutrition and plant fertilizer visit our page: Plant Nutrition
For more information on NPK fertilizers, visit our Water Soluble NPK Fertilisers page, you can also read more about
Need more information about growing onions? You can always return to the onion fertilizer & onion crop guide table of contents
