How to Breed Mealworms
Mealworms are a staple live food for many pet animals, including but not limited to leopard geckos, bearded dragons, chinese water dragons, various tree frogs and frog species, hedgehogs, tarantulas, scorpions, etc. They are not only easy to breed, but also save much money for the owner in the long run. Here is the method the works best for me.
First you will need a nice container for your colony. I recommend sterilite drawers, or you can use other plastic containers that are wide and not too deep. Sterilite shoebox containers, plastic totes, or even those cheap salad plastic containers work too, as long as its plastic (mealworms can't climb out) and it has ventilation.
Sterilie Drawers make perfect containers
Next, you will need mealworm bedding. Many people use oats, bran, even cereal. My personal preference is oats. Not only are they cheap (I buy generic brand quick oats), but they are also easy to find in stores. You want to fill your container with around 1-3 inches of oats as a bedding. Not only will the mealworms live in this, they will also eat it. Bread can be supplemented occasionally for other nutrients.
You will need to supplement a water source every 4-5 days. I usually add lettuce or a carrot. REMEMBER: MOISTURE WILL MAKE THE OATS MOULD AND THAT WILL KILL YOUR COLONY. Therefore, never spray water on the oats or offer a water bowl. Just take a carrot, and just toss it in the container. The mealworms should eat it. Carrots and lettuce tend to dry up over time, making it easy to dispose and not cause mold. Whereas watery foods such as apples, cucumbers, and potatoes will most likely cause mold and have too much moisture.
Lastly, you will need your mealworms. Go to a petstore and purchase enough for your pet and around 100 for your colony. So, if your pet eats 25 mealworms a week, then buy 125 mealworms.
Okay, now for the breeding part. Empty your mealworms into the container. Keep your containers at room temperatures out of direct sunlight and cold drafts. The mealworms should burrow into the oats. Eventually, you will see some mealworms turn into pupa. They will look like white "aliens" or somewhat like beetles (final metamorphosis stage). Once you notice a pupa, be sure to take it out and put it in a separate small temporary container. Mealworms can eat pupa, so that is why you take them out. I keep my pupa in a small plastic bowl. The pupa will not eat or move during this stage. After around 1 week - 2 weeks, the pupa should molt into a beetle. Now, move the beetle(s) to a new container. Add oats like before and add a water source. I find that beetles like more watery foods, so I add apples, but I add them with caution because they make the oats mold easily. Otherwise, carrots/lettuce will suffice for them too. By now, you should have 2 containers. One that contains mealworms that haven't molted into pupa yet, and a container that contains all your beetles. The beetles will lay eggs into their substrate. These eggs are extremely hard to see. My rule of thumb is, after 2-3 weeks of the beetles being their original container, remove the beetles and put them into a new, fresh container with oats. Their old container will have all the eggs they have laid. The best method is to use 3 containers. You will have one container with mealworms, one with beetles, and one to put the beetles in every 2-3 weeks. Of course, you also have the mini container to put pupa in. Within 3 weeks or so, you should see very tiny mealworms in the beetle substrate. Add a carrot to give them water. Great! You have just learned how to breed mealworms. Now the cycle will continue again. In around 3 generations you should have enough mealworms to feed your reptile or other pet.