Fertiliser Quantities for Greenhouse Tomato 100 x Concentrate Stock Solution – Run To Waste Galuku Cocopeat Growbags (kg/1000 L water)

From the above formulas, the typical nutrient element composition is outlined below when assuming standard element concentrations for each fertilizer and dilutions as outlined above.

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Notes – Guidelines for use:
The four formulas are designed for the individual phases of plant growth. The saturation solution is designed for new growing media and application prior to planting to charge the root zone environment.

The two starter solutions are designed for pre-flowering to second or third truss flowering phase (0-5 weeks) and then fruit filling phase (5 to 8 weeks).

The standard solution should be used for the rest of the cropping phase.

With a heavy fruit load, reduce Calcium Nitrate to 90.0 kg and increase Potassium Nitrate to 30.0 kg and raise Magnesium Sulphate to 60.0 kg at 2 weeks prior to picking for the first two trusses.

Thereafter, revert back to the standard solution but also rely on analysis to determine the most suitable management.

In all cases, run off solution and leaf analysis should be conducted to determine optimal nutritional management of the plants. It is advised to conduct this on a regular basis to identify trends in the nutritional uptake.

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Electrical Conductivity
The electrical conductivity supplied in the drip water will depend on the phase of growth, environmental conditions, crop performance, fruit load, varietal requirements etc.

The electrical conductivity of the drip water must be controlled by the grower. In hot weather, high light conditions, weak or highly generative growth use a lower electrical conductivity. With low light, cool weather, soft growth use a higher electrical conductivity.

In general, run off from the bags should be measured and recorded.

Electrical conductivity readings of 2.5 to 4.5 dS/m in run off are acceptable under certain conditions. Avoid high and low electrical conductivity readings for extended periods unless conditions warrant them.

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pH
The pH of the drip water should be applied at 5.5 to 6.5. The run off should be maintained at 5.8 to 6.5. If the pH is higher in the drip and run off, Phosphoric Acid 81% should be added to the B solution at 1.0 L and then the pH monitored in the drip water and run off solution. If pH is still high continue to add Phosphoric Acid 81% gradually until 2.0 L of acid is used, further additions will require modifications to the feed solution supplied to plants.

Future B solutions will need to be modified to reduce the total amount of phosphorus supplied with 2.0 L of Phosphoric Acid 81%. For 1.0 L of Phosphoric Acid 81%, remove 3.4 kg of Mono Potassium Phosphate and add 2.2 kg of Potassium Sulphate.

Never use more than 6.0 L of Phosphoric Acid 81%, seek further advice on long term pH management of the nutrient solution and run off.

Under rapid growth and nutrient uptake, the pH may rise. This can be regulated by the addition of Ammonium Nitrate, never use any more than 1.5 kg per 1,000 L extra unless analysis confirms suitability.

When modifying the pH and electrical conductivity, make gradual changes to achieve gradual changes to the growing media and root zone.

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Disclaimer
The information provided is given in good faith as a general guide only. Significant variation in local climate, greenhouse environment, cultural practices, variety, managerial conditions and other variables are likely to influence crop performance. No liability will be accepted by Galuku Pty Ltd or its representatives for the lack of perceived or actual performance in response to the information provided.