Citrus nutrition – growth, yield, quality.

The nutrients – making the fertiliser choices

Nutrient

Removal

kg/tonne

Potassium 1.6-2.6

Nitrogen 1.2-1.8

Calcium 0.5-1.0

Phosphorus 0.2-0.3

Magnesium 0.1-0.2

Dry matter = 13%

Choosing the right inputs & eliminating the wrong

Nitrate sources

Ammonium sources

Urea

Mixed nitrogen

sources

Nitrogen reactions

Potassium

Nitrate

Sulphate

Thiosulphate

Chloride

Calcium

Nitrate

Thiosulphate

Chloride

Phosphorus

MAP

MKP

Ammonium polyphosphate

Superphosphate

DAP

Magnesium

Nitrate

Sulphate

Thiosulphate

Young trees or

fruit production

DRIP IRRIGATED MANDARIN FERTIGATION PROGRAM

DATE

Fert Quantities 1.00 Ha Fert Quantities

12.00 Ha Easy N POT MAP CALCIUM VALAGRO Easy N POT MAP CALCIUM MINIMUM

NITRATE. TECH NITRATE FERRILENE 4.8 NITRATE. TECH NITRATE WATER

L/Ha (Kg/Ha) (Kg/Ha) (Kg/Ha) IRON (Kg/Ha) Litres (Total Kg) (Total Kg) (Kg) VOLUME

17-Aug-04 0 0 0 0 0

24-Aug-04 0 0 0 0 0

31-Aug-04 20 25 240 0 300 0 2700

7-Sep-04 0 0 0 0 0

14-Sep-04 20 25 240 0 300 0 2700

21-Sep-04 25 2.5 0 0 0 300 30 0

28-Sep-04 20 25 240 0 300 0 0 2700

5-Oct-04 25 2.5 0 0 0 300 30 1500

12-Oct-04 0 0 0 0 0 0

19-Oct-04 25 0 0 0 300 0 1500

26-Oct-04 25 0 300 0 0 0 1500

2-Nov-04 25 0 0 0 300 1500

9-Nov-04 25 0 300 0 0 1500

16-Nov-04 25 0 0 0 300 1500

23-Nov-04 25 0 300 0 0 1500

30-Nov-04 25 0 0 0 300 1500

7-Dec-04 25 0 300 0 0 1500

14-Dec-04 25 0 0 0 300 1500

21-Dec-04 25 0 300 0 0 1500

28-Dec-04 25 0 0 0 300 1500

4-Jan-05 25 0 300 0 0 1500

11-Jan-05 25 0 0 0 300 1500

18-Jan-05 25 0 300 0 0 1500

25-Jan-05 25 0 0 0 300 1500

1-Feb-05 25 0 300 0 0 1500

8-Feb-05 25 0 0 0 300 1500

15-Feb-05 25 25 0 300 300 0 3000

22-Feb-05 25 0 0 0 300 1500

1-Mar-05 25 0 300 0 0 1500

8-Mar-05 25 0 0 300 0 1500

15-Mar-05 0 0 0 0 0

22-Mar-05 25 0 0 300 0 1500

29-Mar-05 0 0 0 0 0

4-Apr-05 0 0 0 0 0

Total Fertiliser 60 250 150 300 720 3000 1800 3600

Total Fertiliser Per Ha Old Young

N 25 33 18 48 124 Kg Nitrogen 211 109

P 39 39 Kg Phosphorous 18 7

K 95 95 Kg Potassium 185 50

Ca 57 57 Kg Calcium 58.14 13

Total applied kg/ha N 124; P 39, K 95, Ca 57

fruit sap test or dry matter

Base Fertiliser

Platinum Plus or Rustica Plus spread about 4-6 weeks prior to flowering @ 300-400 kg/ha Topdressing or Fertigation

Calcium Nitrate can be spread or banded along the treelines @ about 150 kg/ha soon after fruitset and repeated about 4-6 weeks later. Alternatively, fertigate the calcium nitrate @ 50-70 kg/ha at 7-10 day intervals 5 or 6 times to achieve the same overall total application of 300 kg/ha. After completing the calcium nitrate applications, follow-up with potassium nitrate spread or banded along the treelines @ about 150 kg/ha Alternatively, fertigate the potassium nitrate @ 50-70 kg/ha at 7-10 day intervals 2 or 3 times to achieve similar overall total application of 150 kg/ha. Fertigate with Solu-K (potassium sulphate) @ 50 kg/ha or Thio K @ 50 L/ha during later fruit sizing. Micronutrients can be supplied via foliar spray applications of Brexil Combi and fertigation of Trace-It Total and Ferrilene (specifically for iron).