In nature black soldier fly larvae (BSFL) inhabit waste that is exposed to sunlight and rain. We tend to cover our BSF units, blocking out almost all of the natural light and rain that would normally fall on waste found in the open. (I'm referring to the light/rain proof composters we use, I'm not referring to keeping the units in the shade which is usually the best choice) There are benefits to covering the colony including keeping excess rain and predators out and keeping moisture in, but are we losing out on some benefits of these naturally occurring conditions?

The ultraviolet (UV) rays of the sun are known to have powerful disinfectant properties. In most cases we wouldn't want direct sunshine to fall on the colony, mostly because it might cause overheating, but perhaps some indirect UV rays would help control undesirable bacteria. Instead of using opaque buckets, totes, and other materials to build our BSF units with, we might want to consider materials that let some indirect natural light fall on the waste. Totes and buckets are available made from translucent plastics and we might even consider installing glass windows.

Rain falling on naturally occurring waste may help oxygenate and disinfect it. The mechanical action of rainfall may also help by washing away the very fine, finished BSF castings. I have usually flushed my BSF with water on a regular basis, which is probably why I put so much emphasis on good drainage.

Typical BSF composter designs seem like they keep heat in due to the use of non-breathable materials, and keep light and rain out. I think we might benefit from keeping in mind the possible effects of more closely reproducing the conditions found in nature. This is just food for thought.

hermetia illucens, black soldier fly