Nairobi, Sept. 14 -- Africa has spent decades trying to help farmers produce more. That work still matters. But it is no longer enough.

The next agricultural revolution will not be won only in fields. It will be won in the spaces between the farm and the market: in warehouses, aggregation centres, cold rooms, pack houses, repair workshops, processing facilities, logistics firms and rural service businesses.

That is Africa's missing middle. And one of the most overlooked parts of it is not a road, a warehouse or a cold room. It is the technician who keeps the system working.

A cold chain is only as effective as the technicians who run it. A processing plant depends on skilled operators and maintenance teams, while warehouses rely on exp...