Black soldier fly — a small insect with a long shadow

The economics of fish farming in Malawi turn, more than anything else, on the cost of feed. A pond can be dug, a hatchery can be built, training can be delivered — but if the feed cost per kilogram of fish produced is too high, the farmer is not in business. Black soldier fly larvae are one of the most under-used answers to that problem in Malawi today.

Hermetia illucens — the black soldier fly — is a tropical insect with no taste for human food, no appetite for biting people, and an extraordinary capacity to convert organic waste into protein-rich biomass. Their larvae are voracious; their lifecycle is short; their unit economics are kind to a smallholder budget.

§ IWhy BSF, why now

Conventional fish feed in Malawi often relies on imported fishmeal, which is expensive and price-volatile. A BSF unit on the farm — even a modest one — substitutes some of that ingredient with home-grown protein. The economics are not theoretical; they are visible in a feed budget within months.

• ¶Larvae are produced in 7–14 days from substrate to harvest.
• ¶Substrate can be sourced from kitchen waste, brewery residues, market leftovers and agricultural by-products.
• ¶Larvae can be fed live or dried into a storable meal.
• ¶The waste that would have gone to a landfill becomes a productive input.

§ IIThree outputs, not one

We sometimes describe BSF as a feed ingredient — that undersells the unit. Our BSF operation actually produces three outputs: live larvae for direct feeding, dried larval meal for storable feed formulation, and frass, the insect compost, which is a rich soil amendment for our vegetable beds. A single unit closes three different loops on the farm.

§ IIIBSF as a classroom

There is another reason we run a BSF unit, and it has nothing to do with feed economics. The unit is one of the most popular stops on the Generation Game Changers programme. In ten minutes a child can watch a kitchen scrap turn visibly into biomass — a circularity lesson that no textbook can match.

If you would like to start a BSF unit — on a farm, in a school, in a community project — we run a short training on it. The economics will surprise you. So will the children.