The MPOB F-series, and how the app picks one.

What the codes mean

MPOB's F-series are compound fertilisers formulated for oil palm on Malaysian soils. Each sack carries the code and its N:P:K:Mg ratio. Every one of them already includes magnesium and boron, which is why the app never tells you to buy kieserite or borate on top — that would be paying twice for the same nutrient.

The high-K variants — Xtra K, Super K, F5 Super — are the baja buah. Potassium is what a fruiting palm burns through fastest, so once a lot starts bearing, the app switches it to the high-K product of its soil family.

Soil picks the family

When you add a lot you choose one of four soil types. That choice, plus whether the palms are fruiting yet, is the whole product decision:

Age sets the dose

You tell the app roughly how old each lot's palms are — a dropdown, not a planting date — and it puts them in one of five bands. Each band has a yearly dose per palm and a default interval between rounds. The yearly total is what stays fixed: if you shorten the interval on a lot, each round gets smaller so the year's total doesn't change.

From kg to bags

Nobody carries 487 kg; they carry ten sacks. The app finishes the sum for you, using the tree count you entered — or, if you didn't, an estimate of about 60 palms per acre.

The recommendation card on each lot shows exactly this line, and the reason under it says which band and soil it came from.

What the app doesn't know

• Your leaf or soil analysis. The rates above are MPOB's general smallholder guidance. If you have a lab result or an agronomist's programme, follow that and use the app to track what you applied.
• Yield history. The dose is by age band, not by how the lot has been yielding. A lot that is under-yielding for other reasons (drainage, pests, ganoderma) will not be fixed by more baja.
• The weather beyond 14 days. The suggested date avoids heavy-rain days within the two-week forecast; further out it simply shows the cycle date.