Tomatoes

A guide to applying nutrients with liquid fertilisers in tomatoes

• Fertiliser options
• Tomato growth cycle
• Fertigation
• Foliar Sprays
• Replacing nutrients removed in tomato fruit

 

Fertiliser options

Fertiliser	Product rate (L/ha)	Nutrients applied (kg/ha)
		N	P	K	S	Ca
EASY Liquids for application at growth stage – Transplant to first flowers (1-4 weeks)
EASY N Topfoliar® Zincsol®	25 L/ha x 4 applications, weekly 3 – 4 L/ha (several foliar sprays, 2 weeks apart) 2 L/ha (several foliar sprays, 2 weeks apart)	42.5
EASY Liquids for application at growth stage – First flowers to fruit set (5-7 weeks)
EASY N EASY PK®	30 L/ha x 3 applications, weekly 50 L/ha x 3 applications, weekly	38.5 1.5	18	36
EASY N EASY Cal® EASY Cal EASY KS®	30 L/ha x 5 applications, weekly 30 L/ha x 5 applications, weekly 5L/ha x 5 foliar sprays, weekly 50 L/ha x 5 applications, weekly	63.7 19.0		75	62.5	27.1
Sub total (approx. kg nutrient per treated hectare)		165	18	111	63	27
If season is extended and disease pressure is under control, consider additional applications as below :
EASY Liquids for application at ongrowing growth – trellis (13 plus weeks)
EASY N EASY Cal EASY KS	20 L/ha (weekly) 30 L/ha (weekly) 40 L/ha (weekly)	8.5 3.8		12	10	5.4

 

Source: Incitec Pivot Fertilisers, 2011

Notes:

1. Please note that these are only general recommendations. Crop vigour, yield expectations and soil and leaf tissue tests should be used to refine the actual requirements of the crop.
2. Base fertiliser makes up 20-30 per cent of nitrogen and potassium requirement. Majority of phosphorus requirement is applied prior to planting.
3. Additional nutrients may need to be considered in the program, such as zinc, boron, magnesium and molybdenum.
4. Product application rates are the total for the growth stage and approximate number of weeks for that growth stage. They may be split into smaller doses for weekly or daily applications.
5. Check the compatibility of fertilisers before trying to apply two products in the same fertigation application. Refer to the Compatibility section for more information.

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Tomato growth cycle

						Fruit growth
					Flowering – set						Harvest
				1st flowers
		Vegetative growth
Seedling / transplant
1	2	3	4	5	6	7	8	9	10	11	12	13
Weeks

 

Source: Incitec Pivot Fertilisers, 2011

 

Fertigation

EASY N, EASY KS, EASY PK and EASY Cal can be applied through the irrigation water, through fixed sprinklers, microjets or drip/trickle irrigation systems.

Sown or transplanted tomatoes initially rely on starter fertilisers.

After several weeks, given warm temperatures, the young plants grow quickly.

Topfoliar may be applied at planting with water through a water wheel to improve initial growth.

At five to six weeks the first flowers will appear. Growth is rapid during the next four to five weeks while the plant is flowering.

At around 10-12 weeks the vegetative growth rate declines and the fruit fills at a constant rate. Colour starts around this period also. Tomatoes can continue to grow and fruit if the climatic conditions remain conducive and the management practices are correctly manipulated, such as irrigation, fertilising, pest and disease control.

EASY N and EASY PK can be applied several weeks after emergence or transplanting. Continue applications of EASY N up to flowering. Don’t apply nitrogen during the peak of flowering.

Apply regular inputs of EASY Cal and EASY KS or EASY PK from post flowering to set and during fruit fill. When the crop is nearing maturity, only apply EASY KS.

In microjet drip systems, inject EASY Liquids® towards the end of the irrigation shift by irrigating for a number of hours, then inject EASY Liquids for 30-45 minutes and follow by flushing the lines with water for another 45 minutes.

Use a similar fertigation schedule for fixed overhead sprinklers.

Make sure plenty of time is allowed for flushing the lines after the fertiliser injection to ensure the nutrients are washed off the crop canopy. Flush the lines for at least as much time as it took to inject the fertiliser.

Do not fertigate when rain is forecast, as nutrients (particularly nitrate nitrogen) may be lost through leaching.

EASY Liquids should be injected on a regular basis during the growing season to ensure even growth.

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Foliar sprays

Topfoliar, Zincsol and EASY Cal can be foliar sprayed in tomatoes at strategic growth phases.

Topfoliar or Zincsol can be applied to young plants when there is sufficient canopy area and just prior to first flowers.

Topfoliar should be applied at 300-400 ml/100 L of water while Zincsol should be applied at 200 ml/100 L of water. Zincsol application is important on alkaline soils. Apply with a hand held spray gun, multi-nozzled boom or mister (400-1,000 litres of water per hectare).

In dry seasons or with varieties prone to blossom-end rot, EASY Cal fertigation inputs can be supplemented with foliar sprays. Target the spray at the fruit and apply several times during fruit fill.

EASY Cal can be applied at 300-500ml/100 L of water.

When foliar spraying:

• Do not apply when the temperature exceeds 25°C or when the plants are under moisture stress.
• Use a wetting agent at the recommended rate. This will help facilitate uptake.

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Replacing nutrients removed in tomato fruit

At a minimum, fertiliser programs should replace the nutrients removed by the harvested crop. Removal of nutrients will vary with cultivar, yield, soil type and management techniques such as water scheduling, pest and disease control.

Estimated removal in kg/t of tomato fruit

Yield	57 t/ha	194 t/ha
Nitrogen	1.4 (80 kg/ha)	1.9 (370 kg/ha)
Phosphorus	0.58 (33 kg/ha)	0.43 (83 kg/ha)
Potassium	2.6 (148 kg/ha)	3.2 (620 kg/ha)
Calcium	0.11 (6.3 kg/ha)	0.17 (33 kg/ha)
Magnesium	0.14 (8 kg/ha)	0.15 (29 kg/ha)

 

Source: The Australian Soil Fertility Manual (2000) Appendix 1.

 

Figure 1: Nutrient uptake rates for tomatoes.

Source: Huett, 1985

 

For further information, contact your local Incitec Pivot Fertilisers’ Distributor or freecall 1800 009 832.

www.incitecpivot.com.au

This is a guide only, which we hope you find helpful as a general tool. While Incitec Pivot Fertilisers has taken all reasonable care in the preparation of this guide, it should not be relied on as a substitute for tailored professional advice and Incitec Pivot Fertilisers accepts no liability in connection with this guide. Talk to your local Incitec Pivot Fertilisers Distributor Agronomist about soil testing and arranging a specific fertiliser recommendation that best suits your needs.

® EASY Liquids, EASY N, EASY KS, EASY PK and EASY Cal are registered trademarks of Incitec Pivot Limited. ® Topfoliar and Zincsol are registered trademarks of Top Australia Limited.

Incitec Pivot Fertilisers is a business of Incitec Pivot Limited, ABN 42 004 080 264.

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