How to Breed Mealworms, The Easy Way

You may ask why one would want to breed mealworms. There are several reasons I can think of why some might NOT be interested in breeding mealworms: They are worms! They are smelly, slimy, icky, squirmy, worms! They can get out and infest my home! Or those that have a bit of experience with these insects might suggest they can easily be purchase them from a local pet store or even cheaper in bulk off the internet.

First, let me dispel the assumptions- they are not smelly, slimy, squirmy, and I don’t think they are icky. Their climbing skills are limited to non slick objects. They are slow moving so if you do drop one, you can easily capture it.

Yes, you can order mealworms from a pet store. The Internet also sells worms for as little as $12 a thousand! So why would I want to go through the hassle of breeding them if I can purchase them so easily and inexpensive? Great question.

If you raise small reptiles like I do, or have very small hatchlings such as viper geckos, pictus geckos, or even chameleons, you need to raise your own mealworms! You will find that breeding mealworms provides a great range of sizes perfect for these small reptiles. Young reptiles eat often! You need to have a dependable supply of food just the right size for these young animals to allow them to grow at a healthy rate. By raising your own, you will have several sizes available for your animals.

To begin raising your own mealworms start with about 100 – 200 adult worms. Again, these can be purchased at a local pet store or even from an Internet company. A note that regular mealworms will metamorphoses to a pupa and then into the Darkling beetle.

Prepare the bedding used to keep the worms healthy by using a generic brand of oats and a dry baby cereal. The cheaper the better. I use the oats as a base for the medium. I like to add the cereal as an additional food source for the young mealworms.

Mix the two together – 2/3 oats to about 1/3 cereal. You will want to mix enough to have about an inch or two in the bottom of your container. This will become the base food of the worms. Additional foods such as potatoes, carrots, apples, kale, and other greens can be offered to provide moisture to the worms. The container can be a plastic shoebox, sweater box, or another setup I’ll discuss later.

Once the oats & cereal is mixed together, add the mealworms. Add an egg carton top and bottom and you are good to go. The worms use this egg carton to crawl around on and under. Although mealworms will not climb the plastic walls, I position the cartons away from the edges of the box.

Keeping the mealworms at a constant high 70’s low 80’s and you will soon start seeing pupa developing. I have found with the medium mix described above and other foods offered that the worms will not bother the pupa. Some pupa may turn brown and die but most should turn into beetles. If you want to maximize the output, you can certainly separate the pupa from the worms.

After about 2 weeks of being a pupa, you will start to see a few Darkling beetles appearing under the egg cartons. Again, I have not noticed any predation in my groups, even of the softer pupa by the beetles if they are feed well. The beetles are ultimately what you are striving for in a healthy mealworm colony. They lay the eggs to create new mealworms. The eggs are quite small and it is likely you will never see them as they are sticky and will adhere to the bedding.

Eventually the container will be a mix of substrate, egg cartons, mealworms of various sizes, maybe some pupa, and certainly beetles. From this slurry of activity you can selectively harvest the size of mealworm you desire.

The above technique works well if you need to feed just a few animals. If you have more than a handful of animals, the best way to go about setting up a non-stop mealworm factory is to use one of those plastic filing system found at your local department store. Setup each bin with a culture and you will be pulling all sizes of mealworms-more than you could ever use.

In this setup, I have 6 drawers of mealworms going (the middle bin is used for vermiculite). I don’t use all the worms this unit produces. I let several bins mature to produce pupa, beetles, and eventually more mini-mealworms.

I hope you try this neat way to provide your animals additional foods. Be a bit patient as it does take a little time to see those first micro mealworms.