Establish how much water is being delivered to a set area in a given time.

How do I do that?

Check the water penetration with a core sampler.

Establish how many square metres the watering station will water.

How do I do that?

Establish how many litres per minute are flowing through the main irrigation line.

How do I do that?

Work out how much nutrient needs to be applied per square metre.

How do I do that?

Establish how many litres per minute can be injected under pressure into the main irrigation line.

How do I do that?

Add the appropriate nutrients per square metre to the litres per minute that can be injected in the run time of the watering station.

How do I do that?

Run the irrigation system until the required amount of fertiliser has been applied.