Laterite Soil

Laterite soils are defined by an advanced stage of chemical weathering rather than by a fixed particle-size class. Long exposure to warm, wet tropical conditions strips most primary minerals other than iron and aluminium oxides, producing soils with distinctive colour and chemistry that shape their agricultural potential.

Acidity

Intense weathering and leaching typically leave laterite soils acidic, with low base saturation.

Low fertility and CEC

Iron and aluminium oxides hold nutrients poorly compared with more crystalline clay minerals, giving low natural fertility.

Phosphorus fixation

Iron and aluminium oxides bind phosphorus strongly, a well-documented constraint on productivity without management.

Hardening risk

Some profiles can harden irreversibly into ironstone if protective topsoil or vegetation is lost through erosion or excessive exposure.

Managing laterite soils centres on correcting acidity and phosphorus limitations while protecting the topsoil from erosion and irreversible hardening.

• Apply lime to address acidity where appropriate for the crop and local guidance
• Manage phosphorus fertilization accounting for strong fixation by iron and aluminium oxides
• Maintain vegetative cover to protect topsoil from erosion and reduce the risk of subsoil hardening
• Add organic matter to improve nutrient and water holding capacity

Cassava is well adapted to the low-fertility, acidic conditions typical of laterite soils. Coconut and oil palm are widely grown tree crops on lateritic soils across humid tropical regions, generally with fertilizer and soil management inputs suited to the local conditions.

Soil testing for pH, phosphorus fixation capacity, and depth or hardening risk is important given the high variability of lateritic soils. Local agricultural extension guidance is recommended before major investment in a laterite-derived field.