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Fertiliser
A fertiliser calendar for the year: when to apply, when rain says wait
The cycle sets the rhythm. Weather, on any given week, decides the exact day.
A fertiliser calendar has two layers. The first is structural: how many rounds a year, spaced by the palm’s age-band cycle (90 days young, 120 days mature — see our dosage-by-age guide). The second is tactical: which actual day, within the window each round opens, is worth choosing.
Laying out the rounds
Once you know a lot’s cycle length, the year’s rounds are simply the last application date plus that interval, repeated forward. A mature lot on a 120-day cycle gets three rounds a year; stagger multiple lots so they don’t all fall due in the same week if you’re doing the spreading yourself.
What rain does to a fresh application
Freshly broadcast fertiliser needs some rain to dissolve and carry nutrients into the root zone — but too much, too soon, runs it off the surface or leaches it below where roots can reach it. The two failure modes:
- Applied into heavy rain the same day: runoff risk, especially on sloped ground — fertiliser washes away before it dissolves in place.
- Applied into a dry spell with nothing after: the granules sit on dry soil undissolved, doing nothing until rain eventually comes.
Reading a fertiliser window
The ideal day has light-to-moderate rain in the days that follow — enough to dissolve the fertiliser into the soil without a downpour heavy enough to wash it off first. Because rain is forecastable roughly a week or two out, this is the one part of the schedule worth timing rather than fixing to a set date.
Building the calendar
| Step | What it decides |
|---|
| 1. Palm age band | Cycle length: 90 or 120 days |
| 2. Last application date | Where the next round’s window opens |
| 3. Forecast within the window | The best day inside it, not just the earliest |
Frequently asked
How wide is the window for a round, in practice?
Roughly a fortnight either side of the target date is normal — fertiliser timing is far more forgiving than a harvest round, which needs to happen within a few days either way.
Should I apply right before or right after rain?
Right before a forecast of light-to-moderate rain over the following few days is the ideal; heavy rain on the day itself is the case to avoid.
Does this change during the dry season?
In a genuinely dry stretch with no rain forecast at all within the window, it’s often better to apply anyway near the end of the window than to push the round out indefinitely waiting for rain that may not come.
Let the weather forecast pick the day
SawitSync scores the coming two weeks for each lot’s fertiliser window and suggests the best day — and says why.
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