A complete fertilization program for onion

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