In the United States alone, Americans waste $160 billion which is nearly 30 to 40 percent of the entire U.S. food supply. That's 133 billion lbs. These beautiful little insects have great potential. There are many talented people and state universities studying this very issue. Besides saving the planet, it's FUN, rewarding and profitable to compost your food waste and It's not difficult.
The goal is a daily routine that is simple and easy. These instructions are by no means the only way to do it. If you attempt to compost with BSF you may find this page sketchy and bref. My intention is to get you interested, give you the basics and to help you avoid pit falls. I do not include breeding instructions.
Imagine no wet garbage in your trash! No rotten food smells. No pest insects like fruit and house flies. They kill just about every other thing in the bin that is not themselves including salmonella and E-coli. Wile traditional composting can take months BSFL takes a day . What is left over is sometimes called "Frass". Frass is a valuable, organic fertilizer, Not quite compost and not quite manure. Besides it's potent fertilizing qualities, it has been found to stimulate some plants to produce a natural organic pesticide.
You will need the right containers. Steel is OK but plastic is better. Don't use galvanized. Wood will eventually need replaced and tends to absorb liquids and rot away. Round is best but square will work. The size will depend on the size of your family. Figure 5 gallons per person. So, a 3 person family would need at least a 15 gal container. I like to have two so you can dump one into the other.You should have 5000 grubs per person. That will be enough to compost all the waste in a day and keep it fresh and healthy. So, basically, when you receive your grubs, put them in the container and feed them. That's it.
They eat pretty much everything you eat and many things you don't eat. They do best with variety and balance. Fresh food waste is best but occasional spoiled, moldy food is absolutely fine. (they love to eat mold) Small amounts of meat is fine. Bones and egg shell add calcium to the frass but will linger for years. Coffee grounds are excellent and you can throw in the filter paper, It will disappear or end up cleaned, dry and on the surface. Some foods like onions may take longer but will eventually be eaten. Any rotten parts will go immediately. They don't eat cellulose. (wood, grass, cardboard etc.) Dry things like flour, cereal, grain, seeds are ok, just do not add water. Put it in dry.
Can you do this in your house? Absolutely! In fact, it is preferred. Indoors eliminate many potential problems like temperature control and pests like ants, spiders, raccoons etc. When run correctly, there is no odor. I do it in my cellar. The temperature is very consistent throughout the year. (Up-state NY) A heated garage would work. A convenient location is essential considering a daily routine is necessary.
If it is a hassle to operate, you will not stick with it. To succeed, it must become part of you routines. Finding something that works for you is an important issue. Don't be afraid to try things. Find solutions. Do what works. My wife and I generate approx. 2 lbs of kitchen waste a day. Next to our regular trash bin we keep a smaller version. A little Pop Top trash bin with a small bucket inside. The small bucket is filled every day or so with kitchen waste. I then carry it to the cellar, dump it in a pod,rinse it out and put it back. Done. That's pretty much all there is to do on a daily basis. Occasional duties include removing frass and crawl outs, maintaining population, (re ordering grubs) checking humidity and temperature, turning. There isn't much else to it.
Too wet is the most important thing to learn. Kitchen waste is generally wet. Too wet will not hurt the grubs. However, there are conditions that develop that don't work. Sludge and Anaerobic bacteria. Sludge is like sticky clay. They get locked in it and can't move. Anaerobic bacteria develop. (more on this in the next section.) You must also learn to balance the grub to food ratio. As the grubs grow, so dose the frass level. It's best that they are a little on the hungry side. Since the waste stream IS what it IS, you must have the correct amount of grubs in your pod. Another consideration is that food waste, grain AND grubs will attract rodents. Too dry (a rare condition) will cause the grubs to stop eating or even die. Too cold or too hot will do the same.
Anaerobic, meaning without oxygen and aerobic meaning with oxygen is very important concept to understand with BSF composting. Aerobic (with 02) is sweet. Anaerobic (without 02)is evil. Your colony must have acquitted oxygen else you will create a "stink box" and ,trust me, you don't want to do that. Anaerobic conditions allow a totally different set of bacteria to proliferate. Besides a smell that will stop a mule at 40 paces, it will generate methane gas. (flammable greenhouse gas) So, keep it dry, keep it dry, keep it dry.
Don't be afraid to "turn" your pod so that what was on the bottom, is now on the top. This is a good practice considering food tends to sink in a pod .Turning, causes the food to be re eaten and adds oxygen The frass becomes more consistent.It also evens out the humidity and temperature in the colony. The grubs are very tough and don't seem to be stressed,just do it slowly. A half turn every third day is adequate.
When washed, the grubs themselves have no odor at all. Odor is directly related to the condition of the Frass. The frass, obviously, is made of what you add to the pod. Spoiled food and mold is the first thing to be eaten so associated odors are not an issue. A spent lime or lemon will actually act as an air freshener wile it lasts. Generally, a light odor of the Fresh condition of food scraps is evident. There should be no mold growing. If a foul odor is detected, something is going wrong. So, by all means, use your sense of smell to diagnose the condition of your colony.
I recommend 5-6000 grubs per person. Figure 1 person creates 1 lb of food waste per day and the cycle 14-21 days means approx. 5 gallons of container is needed. (for each person) For the colony to generate it's own heat, a minimum population of 10,000 is recommended.
The grubs can survive a wide temperature range. They prefer warm. When cold, they stop eating. When a pod goes "cold" something
is wrong. Either there is not enough grubs or they have reached the end of their eating cycle. They self regulate the temperature
however, a fully oxygenated bin with proper humidity will also add heat just from the natural process of composting. When this
happens, the grubs get out of the way. A hot "core" develops and the grubs go to the sides. This is where "turning" helps. Expose
the hot core and break it up. This will spread the heat and humidity, add oxygen and make food available again. My cellar, (where I keep my
colonies) stays around 65 F (ambient) year round. This is good for operation. The pods, (I have dozens) are 104 F. They self heat to 104 F.
Grubs outside the pod stop moving. (too cold for them) so they stay inside.
As I mentioned , too wet is a big issue. If you have the condition you must add something very dry to re balance the humidity. This means keeping a drying agent on hand at all times. I recommend Table Bran. It can be purchased at your local feed store for 10 cents a lb.It works excellent and s converted to frass worth $10.00 / lb! Flour, cereal, grain etc will work also. Cat litter (with manure) is acceptable but they don't eat it (they will eat the manure) and it will tend to fill up the pod. The proper humidity is describes as "slightly "damp. No visible liquid. Light , fluffy, granular. After a wile you will will be able to make good judgment on humidity by just the look, small, or feel. You can also use a soil hygrometer. (about $14.00 on EBay.) On rare occasions you may add water. (probably never)
Eventually you deal with Frass. You can simply put it out side in a pile. Any remaining grubs will complete their cycle and leave. However, frass is a valuable commodity. It is worth $10.00 a lb! Besides being a potent fertilizer it can stimulate some plants to produce natural, organic insect deterrents. Apparently the plant thinks it is being invaded by insects and responds accordingly. Store your frass in paper or a woven grain sack. This will allow it to breath. (remember aerobic!) If you store it in plastic, poke allot of pin holes in it. To recover your frass you can screen it if you want with 1/8" mesh or just use it as is.
There is two basic methods of management. I use both. Batch and Continuous. For the purpose of composting, I recommend the continuous method. The continuous method involves overlapping your orders of grubs so that you have a mix of sizes at all times. The larger "crawl-outs" (black ones) will want to leave the bin so, you provide a way for them to crawl out into a bucket. Small amounts of frass is occasionally raked off the surface as you add food scraps. This can go for many weeks but eventually you will want to start over as the inedible parts accumulate. Eggs shells, bones, onion skins, coffee filters etc.tend to migrate to the surface and can be removed. This insect is native to most areas so releasing them into the environment is not a problem. In fact, desirable. During the summer, they may breed and inhabit your property (if you are lucky) and if you have manure available, else you will probably never see one. Regardless, they are harmless, clean, beneficial insects that will reduce filth flies and other pests,greatly reduce the size of the manure pile and create food for other wild creatures. The result is a more productive farm. In winter, some of the grubs may survive till spring if the compost pile is large enough to generate some heat.
There are many techniques of separating the grubs from the frass. The way you process your pod is directly related to what you plan to do with the grubs and the frass. For the purpose of composting, processing it is unnecessary. However, the grubs and the frass are valuable assets. Example: if you raise chickens, just let them pick through the pile. They will clean the frass and do the work for you. You can spread the spent bin material (bugs and all) on your lawn or garden AS IS.(lightly) Any remaining grubs will not be a problem. If you feed fish, you may want them as clean as posible. There are many uses for this insect (including selling them). Weather separation is necessary or not will depend on the use. Separation can range from a simple screening to fancy custom equipment. I use several techniques and also rinse the grubs because I sell them to exotic pet owners. However, washing is unnecessary for grubs sold as composting worms.
(The Migration) When BSF are done eating they turn black and try to leave the bin. Their nutritional value reaches it' peak especially with concern to calcium. This is obviously very convenient and useful if you plan to use or separate your grubs. They march out of the bin in a clean state. In a continuous process, the grubs separate themselves. They evacuate their gut, stop eating and "crawl-out" on their own. Providing a method of escape is necessary. A ramp of some design will allow them to climb out and drop into a container.
Adult flies are rare in a properly run compost bin but they are never a problem. If you see adults emerging from your bin it's time to re start the pod. At 65 F (a cellar) they can't fly. They only live a a week or so. They don't bite, sting or carry pathogens. They don't bother humans of animals and they don't eat. They are easy to capture.
I encourage people to breed their own BSF but It can be technical and difficult. Methods vary greatly and it's a matter of finding a system that works for you. Besides breeding you must get them to lay eggs and the newly hatched grubs are delicate and need special care for a wile. I do not recommend breeding if you just want to compost. It's a totaly different set of responsibilities and takes homework and perseverance.