Sustainable Chicken Keeping: Raising "Grubbies" to Feed Poultry at Home
Updated: Feb 8

If you think eggs are expensive now - this is only the beginning. If you are raising laying hens, it is no secret that bag feed ranges from 19-32 dollars a bag, driving homegrown eggs well over the dollar-an-egg mark. With the rising grain cost and egg farms culling birds that test positive for bird flu, prices will continue to soar, causing demand to crash. When demand drops, so will the number of kept commercial laying hens, causing a ripple effect that further delays market recovery. Egg prices may not come down for years as long as global politics have a grip on fertilizer prices or until grain farmers adapt to regenerative farming practices.
As a homesteader, I have been raising poultry for two decades, and until the pandemic of 2020, I could always afford feed for my poultry. The added war in Ukraine created a global grain shortage that made feed expensive, and bulk grain was unavailable in my county and surrounding county co-ops. I knew in 2020 that if I couldn't afford to raise poultry on pasture with the cheapest unprocessed grain possible, the entire food chain would be in short supply.
This made me realize that my homestead wasn't as independent as it needed to be. Although I grew a great deal of fresh organic garden vegetables to raise my poultry all summer, I still depended on the local co-op for the additional feed to provide the nutrients needed. It is impossible to raise poultry without grain to provide enough protein and fiber to keep them full. Chickens that do not have a full crop will eventually start to peck, feather pull, and cannibalize one another as they need a full crop to keep a gizzard working correctly. I had to find another way to supplement their diet to keep them alive, healthy, and in laying condition for those wonderful farm-fresh eggs.
I researched all grains, beans, and legumes I could grow and harvest by hand. Nothing would equal the 12-15% protein needed to raise mature birds and provide the energy required to produce eggs. How could I keep my poultry alive so that I had something to eat? I wasn't about considering the alternative suggested by Bill Gates, the UN, and World Economic Forum to eat bugs. Still, it made me question what was in those recommended bugs they were willing to commercialize for human consumption. What I found was an affordable gold mine in poultry feed that I could grow at home.
Black soldier fly (BSF) grub farms are popping up worldwide. They are being funded by the millions by well-known global organizations as a new alternative to feed humans and livestock due to their excellent protein, vitamin, and mineral bioavailability. Black soldier fly grubs contain 39-48% protein and are full of vitamins and minerals when fed a healthy diet. This means it wouldn't take giant amounts of grubs to provide poultry their 12-15% protein to thrive on pasture with or without grain supplements.
(1) Black Soldier Fly Nutritional Value
Isn't a fly grub a maggot? Well, technically, yes, but in my mind, a maggot is something that eats trash and rotten, disgusting things. Black soldier fly larvae can be vegetarian-fed and prefer clean, fresh food sources like cucumber, squash, peppers, tomato, and leftover table scraps. I lost the heebie-jeebies quickly when I discovered that they are no more disturbing to handle than earthworms and quite a bit cleaner. They aren't even slimy.
Black Soldier Fly originated in South America but have adapted to live in temperate climate worldwide. In the spring and summer months, they can be lured to lay eggs in pieces of cardboard suspended over sour grain and compost piles. I tried for months to catch some here where I live in Kansas but never had any luck. I had to buckle down quickly because my birds were starving.
Newly hatched black soldier fly larvae (BSFL) can be purchased by mail from several reputable sources. Fly eggs are distributed into bait cups of damp bran and have no problem living through the shipping process. These companies will not ship when the weather does not support it. Once you have purchased larvae, you can choose to grow them out to feed your poultry which would be very costly to continually buy freshly hatched larvae or raise the flies yourself to go full scale. I ordered my fly brood from PopwormsLIVE! Here is the link to their webpage.
(2) PopWormsLIVE!
The worms are very tiny on arrival and, in some cases, may not be visible to the eye as eggs in the shipping media continued to hatch for days. I placed container contents in a bucket with a small amount of fresh, cooked, cooled rice, a little corn flour to keep the moisture content correct, a few slices of cucumber, and a few slices of zucchini. Within a few hours, I would lift the cucumber and zucchini slices to see the tiny grubs chowing down on the slices by the thousands.
The grubs have a generous learning curve and are very forgiving. The substrate needs to be 30-70% moisture. Not too wet and not dry, think potting soil. If the substrate is too wet, they can crawl out of the bin or buckets you raise them in, as the tiny hairs on their body can grip the walls of almost any surface. Using flour on the walls can hinder this if you accidentally get your substrate too wet. Substrates can range from woodchips and sawdust to rice and bran hulls. I use ground whole oats as the drying action works best with high moisture feeds such as cucumber, and as the ground oat grain moistens, they can also consume that. They prefer the same temperature as humans but thrive at 82ºF. Cooler temperatures slow their growth, and the grubs prefer the dark. These grubs grow so fast that there is a daily difference in size. It only takes two weeks to raise a grub to the fatted stage when they are healthiest for serving up as dinner for your livestock.
*NOTE: Digging deep into research for potential health consequences, I learned that fully pupated and dark-colored grubs should NOT be fed to poultry. The grub's outer layer has a high chitin content at this stage. Chitin, also known as chitosan, inhibits fat-soluble vitamin absorption. This will slow the growth of your poultry and create leaner chickens. Laying hens need fat to lay healthy eggs regularly, and lean poultry does not make tender & juicy table fare.
Grubs in the fatted stage are the healthiest for your livestock just before they pupate. Black soldier fly companies are investing large amounts of money in figuring out how to reduce the chitin content so that it may be used for human and other ruminant livestock consumption. These companies also use the harvested chitin to manufacture chitosan for clearing alcohol before distilling and to sell as what I would consider an unhealthy weight loss supplement due to its vitamin-blocking capabilities that starve fat cells.
(3) Effects of dietary chitosan on fat deposition and lipase activity in digestion in broiler chickens
How did I know when the grubs needed more food? They come to the surface and dance in a frenzy. They are not hard to feed. The grubs release a pheromone when they find a good source of food. Other grubs join and create heat, which helps generate more pheromones, and most of the grubs will congregate in "hot spots." To catch the grubs out of the substrate, I use a food such as a pepper, squash, coffee grounds, or piece of meat and lay it on their bedding. The grubs will be teaming under or inside the food in a few hours. I scoop them up or out of the food and place them in a sieve to sort the smaller worms back into a new feed bin to continue to grow out. It didn't take long before I had a system to feed my growing meat chickens 2-6 cups a day. This equates to POUNDS of protein daily!
I watched several hours of YouTube videos before developing the way I thought would suit me best. There are many ways to grow grubs; you can make it as simple or as complicated as you want. There are giant Black Soldier Fly bins for sale for around $700.00, and you can make a bin at home for under $40.00 (PVC and storage bins are expensive). All these options allow the grubs to pupate and crawl from the container in the pupa stage that is high in undesirable amounts of chitin.
I knew I wanted to hatch out the flies, to grow millions of grubs, but I also didn't want to pay a fortune for the available BSF farming kits, so I made my own from affordable items on Amazon.
Here is what I did.

I set up a system in an outbuilding to keep this mess out of the house and to protect it from raccoons. If you overfeed your grubs, they can get pungent. Done correctly; it smells like fresh soil. I knew I would go big with my plan, so I purchased a deep wall kiddie pool and filled it with a few inches of two-year-old wood chips. I tilted the table and added a drain, as well-fed grubs can create a good deal of moisture if the substrate isn't adjusted with dry content to control moisture build-up. That is what the tubing is for. I fed the grubs fresh garden vegetables that I cut in half to make it easier for them to eat. They LOVE Armenian cucumbers, and they are so easy to grow! I no longer use the drain method as I tend to them daily to keep the moisture content correct with finely ground grain. They only require a few cups a week. Looking closely, you can see the pupated grubs in this next photo.

It was amazing how fast they would eat the things I put in the bin, and when they were chewing on food, it was audible when you entered the room. It sounds like bacon sizzling. In three weeks, the grubs pupated, and I thought I would catch the pupated grubs by letting them climb the tubes, as hundreds of YouTube suggested. This method did not work. Most preferred to rest and finish their pupating process right where they were. So I adapted to their likeness. I wanted healthy flies to lay lots more eggs for millions of grubs.

I bought a large mosquito net and covered the pool to let the flies grow out. This time I tried to use the tube to catch the flies to move out of this area into a nicer enclosure to breed. Again, the tube was unsuccessful. These flies are not like house flies. They are slow. You can catch them mid-air and pick them off any surface they land on if some escape. They are drawn to the light, so if some escape, turn off the lights and open the door. They go right outside when shooshed with a broom.
To get them to breed, they need a good light source. I used a high-power grow light to start spring seedlings to mimic their daylight, and I was very successful. Regular daylight is significant, but this building was insulated off at the time to keep the 100º summer heat out and to keep my deep freezers from running so hard. I kept the room around 80ºF as they breed best at 82ºF with 80% humidity.