Godavari Delta Crop Health Survey

The problem

GreenFields manages input programmes across 340 smallholder plots aggregated into 1,800 acres of paddy. Their agronomists were covering it on foot and motorcycle, which meant each plot got looked at roughly once every eighteen days – and by the time a deficiency is visible to the eye, the yield penalty is already locked in.

The delta's plot geometry made it worse: irregular boundaries, bunds under a metre wide, and standing water for much of the season.

What we did

We flew multispectral surveys on a fortnightly cycle from transplanting through to panicle initiation, generating NDVI and NDRE index maps per plot rather than per block – so a single underperforming smallholder plot did not get averaged away inside its aggregation group.

Each cycle's index maps were differenced against the previous cycle, and any plot dropping more than one standard deviation below its own trend was flagged for a ground visit. That turned the agronomy team from a patrol into a response unit.

Boundaries were digitised once from a 2 cm ortho and reused all season, which also gave GreenFields a clean plot register they had never previously had.

The outcome

In the third cycle the index maps flagged a contiguous 210-acre zone dropping against trend. Ground truthing confirmed nitrogen deficiency roughly three weeks before it would have been visible on inspection. A corrective top-dress went out within the same spray cycle.

Across the season, flagged-plot visits replaced blanket patrol. Agronomist field-hours fell by about 40% while the number of plots receiving a targeted intervention roughly doubled.

“Their flights picked up a nitrogen deficiency we would not have seen from the bund for another three weeks. That is a full spray cycle of difference on 1,800 acres.”

Neha Bhatt, Agronomy Lead, GreenFields Agritech