A fertigation schedule decides how much nutrient reaches each block, and when. It is not the same as a fertilizer program. The program sets the grade and the dose for the season, while the schedule divides that dose across weeks and across zones. Because drip lines deliver small volumes often, the schedule carries most of the control.
What a Fertigation Schedule Has to Fix
Four items belong on the sheet. They are the grade, the concentration in the tank, the volume per zone, and the interval between rounds. When any one of them stays open, the block either runs short or runs rich. In practice, most growers also add the target EC for each stage.
Split the Season by Growth Stage
Nutrient demand changes with the stage. Vegetative growth pulls on nitrogen, flowering pulls on phosphorus, and fruit fill pulls on potassium. Therefore, rewrite the schedule at each shift. Our NPK ratio guide sets out the logic behind each stage.
Set the Injection Ratio, Not Only the Total
A season total tells you what to buy. It does not tell you what to inject on Tuesday. Split the total into rounds, then set the concentration for each round. Meanwhile, keep the stock tank within a range your pump and emitters can handle. Our injection guide covers dosing equipment.
Match Dosing to Water Uptake
Plants drink more in hot, bright weeks and less in cool, cloudy ones. When uptake falls, a fixed dose lifts the concentration in the root zone. As a result, the schedule should track irrigation volume rather than the calendar alone. Record the EC before and after each round, as our EC and pH notes describe.
Record What Each Zone Receives
Blocks differ. Soil texture, slope and emitter spacing change how far a dose travels. However, one shared log still works when it names the zone, the date and the volume. After two or three rounds, the log shows which blocks drift from the plan. Then you can adjust that zone alone instead of the whole farm.
Review Every Two Weeks
A schedule is a draft that improves with use. Review it every two weeks against the log, the crop stage and the water source. Once a change proves out, write it into the next round. Line care belongs to the same routine, and our flushing procedure covers that step. For grade options, see the high-K soluble grade.
Reference: FAO Soils Portal for nutrient management context.
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