Neither larvae nor adults are considered to be agricultural pests or disease vectors. Black soldier fly larvae play a role similar to that of
redworms as essential decomposers in breaking down organic substrates and returning nutrients to the soil. The larvae have voracious appetites and can be used for
composting household
food scraps and
agricultural waste products. Additionally, black soldier fly larvae are an alternative source of protein for
aquaculture,
animal feed, and
pet food. The larvae are produced and processed in industrial-scale
insect factories globally by biotechnology companies such as LIVIN farms InnovaFeed, and
Protix, the latter operating the world's largest insect factory farm in the Netherlands.
As decomposers in composting Black soldier fly larvae (BSFL) are used to compost waste or convert the waste into animal feed. Waste streams include fresh manure and food wastes of both animal and vegetable origin. Fly larvae are among the most efficient animals at converting biomass into feed. they enter a stage called the "prepupa" wherein they cease to eat, and tend to migrate toward cool, dark, and dry substrates to
pupate. This prepupal migration instinct is used by grub composting bins to self-harvest the mature larvae. These containers have ramps or holes on the sides to allow the prepupae to climb out of the composter and drop into a collection area. Black soldier fly larvae are beneficial for use as composters in the following ways: • Their large size relative to houseflies and blowflies allows BSFL to prevent
houseflies and
blowflies from laying eggs in decaying matter by consuming larvae of other species. This means compost systems inhabited by BSFL may be a more human-friendly way to handle food waste when compared to those inhabited by houseflies and blowflies which typically produce a much worse smell. • They are not a pest to humans. Unlike houseflies, adult black soldier flies have greatly reduced
sponging mouthparts, meaning they can only consume liquids such as flower nectar, although they typically do not eat at all. Unlike houseflies, which regurgitate food along with digestive enzymes, adult black soldier flies therefore do not spread pathogens or diseases. • They are not attracted to human habitation or foods. • Significant reductions of
E. coli 0157:H7 and
Salmonella enterica were measured in hen manure after larvae were added to the manure. • They quickly reclaim
would-be pollutants: Nine organic chemicals were greatly reduced or eliminated from manure in 24 hours, making them a potential tool for
bioremediation. • They quickly reduce the volume and weight of waste: larval colonies break apart their food, churn it, and create heat, increasing compost evaporation. Significant amounts of waste are also converted to
carbon dioxide respired by the grubs and
symbiotic/
mutualistic microorganisms. The use of BSFL in a compost system typically reduces the volume of compost by around 50%. Aside from protein production, fly larvae also produce
frass. Fly larval frass is a granulated and odorless residue that can be used as organic fertilizer directly or through conversion by earthworms.
As feed Black soldier fly larvae are used
as feed for pets and livestock animals. The harvested
pupae and prepupae are eaten by
poultry, fish,
pigs, lizards, turtles, and even dogs. At the pupal stage, black soldier flies are at their nutritional peak. They can be stored at
room temperature for several weeks, and their longest
shelf life is achieved at . In November 2025, the largest insect farm in Northern Europe, Enorm Biofactory, went bankrupt, despite €55 million in funding. A 2024 analysis indicated that the majority of investment in insect farming had been directed towards companies farming black soldier fly larvae (59% of disclosed investments). However, a significant proportion of these investments (around 36%) have gone to firms that have ceased operations or entered court-supervised restructuring. While investment growth was rapid prior to 2021, recent trends show a 65% decline between 2022 and 2024, reflecting a challenging investment environment.
As human food Records of human consumption of
H. illucens are difficult to find. It is a multi-chambered plastic machine that looks like a kitchen appliance and can produce of larvae or two meals in a week. The taste of the larvae is said to be very distinctive. According to Unger, "when you cook them, they smell a bit like cooked potatoes. The consistency is a bit harder on the outside and like soft meat on the inside. The taste is nutty and a bit meaty.
For producing grease BSFL can be used to produce
grease, which is usable in the pharmaceutical industry (e.g. in
cosmetics,
surfactants for shower gel), thereby replacing vegetable oils such as palm oil. It can also be used in fodder.
For producing chitin BSFL can be used to produce
chitin. Chitin is used in shipping as an agent against
biofouling. It is also used in water purification.
For producing organic plant fertilizer Material left over after the larval waste decomposition process (
frass) consists of larval faeces, shed larval
exoskeletons, and undigested material. Frass is one of the main products from commercial black soldier fly rearing. The chemical profile of the frass varies with the substrate on which the larvae feed, but in general, it is considered a versatile organic plant fertilizer due to a favorable ratio of three major plant nutrients:
nitrogen, phosphorus, and potassium. BSFL frass is commonly applied by direct mixing with soil and considered a long-term fertilizer with slow nutrient release. In addition to its nutrient contribution, BSFL frass can carry further components that are beneficial for soil fertility and soil health, such as chitin Debate is going on whether the frass from BSFL rearing can be used as a fertilizer in a fresh state or has to undergo further composting before its application. Some assume that further composting would lead to the reduction of potential
phytotoxic properties. In the
European Union, insect frass has to be treated for one hour at before commercialization for safety reasons, the same as other animal manure products. However, a 2024 life cycle assessment commissioned by the UK Department for Environment, Food and Rural Affairs (DEFRA) concluded that the environmental impact and safety of frass at a large scale remain unknown due to a lack of standardisation, field-scale trials, and data on nitrogen behaviour.
In bioremediation Recent research in the field of
entomoremediation shows the potential of this insect for purification of biomass contaminated with heavy metals. Larvae of
H. illucens were used in a bioremediation experiment, in which they consumed up to 49% of dry weight corn leaves polluted with cadmium or zinc, for 36 days.
Potential use in biodiesel production H. illucens could be a feasible feedstock for biodiesel production.
Farming Larval colonies The main difficulty in farming black soldier fly larvae (BSFL) comes when obtaining larvae or eggs to start or replenish the colony. This is usually done by enticing the soldier flies to lay eggs in small holes over a grub bin. Adult flies lay clusters of eggs in the edges of
corrugated cardboard or
corrugated plastic. In some regions, starting or maintaining adequate larvae colonies is possible from wild black soldier flies, but pest species such as houseflies and blowflies are also drawn to many of the foods used to attract soldier flies, such as fermented chicken feed. In tropical or subtropical climates, black soldier fly adults might breed year-round, but in other climates, a greenhouse may be needed to obtain eggs in the cooler periods. Black soldier fly larvae are quite hardy and can handle more acidic conditions and higher temperatures than
redworms. Larvae can survive cold winters, particularly with large numbers of larvae, insulation, or
compost heat (generated by the microorganisms in the grub bin or compost pile). Heat stimulates the larvae to crawl off, pupate, and hatch, and a great deal of light and heat seem to be required for breeding. Many small-scale BSFL farmers start their larval colonies from eggs deposited by wild soldier flies.
Space and shape Newly emerged soldier flies perform the beginning of their mating ritual in flight. The male grabs onto the female, and then grasps the female's ovipositor with his genitals. They mate while stationary and connected. German scientists have successfully bred soldier flies in a space as small as 10 liters.
Heat Adults typically mated and oviposited at temperatures of or more. Around 99.6% of oviposition in the field occurred at .
Light Quartz-iodine lamps have been successfully used to stimulate mating of adults. In particular, mating success of reared black soldier fly can be dramatically increased by exposing the adults to light that is particularly rich in wavelengths near 440 and/or 540 nm and has an irradiance that is an appreciable fraction of the intensity of full sunlight. In tropical conditions, morning direct sunlight is optimal for emergence, mating, and egg laying, with indirect sunlight often preferred before and after mating.
Humidity Humidity at 70% is considered optimal for all stages of their lifecycle. Substrate was found to be unnecessary for pupation, but substrate is thought to act as a regulator for humidity, which prevents desiccation. A 93% emergence rate was observed when humidity was held at 70%.
Black soldier fly larvae and redworms Redworm farmers often report black soldier fly larvae in their worm bins. Black soldier fly larvae are better at quickly converting "high-nutrient" waste into animal feed, while redworms are better at converting high-
cellulose materials (paper, cardboard, leaves, plant materials except
wood) into an excellent
soil amendment. Redworms thrive on the residue produced by black soldier fly larvae, but larvae
leachate ("tea") contains harmful
enzymes and tends to be too acidic for worms. The activity of larvae can keep temperatures around , while redworms require cooler temperatures. Most attempts to raise large numbers of larvae with redworms in the same container, at the same time, are unsuccessful. Worms have been able to survive in/under grub bins with bottoms that open into the ground. Redworms can live in grub bins when a large number of black soldier fly larvae are not present. Worms can be added if the larval population gets low (in the cold season) and worms can be raised in grub bins while awaiting eggs from wild black soldier flies. As a feeder species, BSFL are not known to be
intermediate hosts of
parasitic worms that infect poultry, while redworms are host to many such species.
Names and trademarks BSFL were developed as a feeder insect for exotic pets by D. Craig Sheppard, who named the larvae
Phoenix Worms and began marketing them as pet food. In 2006, Phoenix Worms became the first feeder insect to be granted a U.S. registered
trademark. Other companies also market BSFL under such brand names as Usefullfly Chengdu (UAE-CHINA),NutriGrubs, Soldier Grubs, Reptiworms, Calciworms, BIOgrubs, and Obie's Worms (Canada), Zeronix (Russia), Polezniye Biotechnologiy (Russia) ). In Africa, they are marketed as live feeder, meal and oil by ProtiCycle for animal feed, pet food for dogs and cats, and food for fish such as tilapia and catfish. == Possible natural enemies ==