Worms 101

There are always a lot of questions when talking about worms. Like what kind should I buy? What do they eat? How do they reproduce? And so on. So let’s dive in and answer some of the more basic questions starting with basic worm biology.

Kinds of Worms

There are approximately 2,700 different types of worms but only a few that will work well in a worm bin. Some people think that when you want to start your worm bin the best idea is to go out into the garden and dig some up. Whatever worms you find in the ground should work just fine in a worm bin right? Well the truth, is not really. There are thousands of different types of worms out there and only a few will really work well for you in your bin. Different types of worms do different things and live in different environments. The environment that we will be creating in a worm bin is very specific and we will need a worm that will work well in that environment.

Night crawlers: These are the worms that you most often find in a garden when you are digging around in the soil. They are mostly brown or darker shades of red and can grow quite large around 6 inches and I have seen some that were a quarter inch in diameter in my outdoor compost heap. The problem with night crawlers is that they prefer to be solo and not around one another unless they are breeding. Night crawlers also have a tendency to burrow down deep and in a worm bin that is not really an option.

Night Crawlers

Red Wigglers: These worms are much smaller than the night crawlers and tend to be a reddish color giving them there name, although they can be shades of brown also. Red Wigglers prefer to be in large groups and are often found in huge masses with hundreds of worms in the same few cubic inches.  They love to live close to the surface and can sometimes be found outside immediately under compost piles or manure piles. As a result of these qualities Red Wigglers are the best choice for worm bins most of the time and are the ones that I would recommend you use.

Red Wigglers

Worm Sex

Worms are hermaphroditic meaning that they have both male and female sex organs. Two worms are still required for breeding though. During breeding, two worms will line up in opposite directions and trade sperm cells. The worms will than crawl away with the others sperm and fertilize their own eggs with the other worm’s sperm cells. The worm will then form a cocoon with their eggs and the others worms sperm cell. The cocoon will hatch in about 11 weeks depending on the temperature and conditions.  A cocoon will hatch between 5 and 6 baby worms. Worms can breed 3 times a week. So you can see that worms can grow their population very quickly. New born worms will not reach sexual maturity for about 2 months.

If you work out the math, you will think that worms should have taken over the earth by now. They have an immense ability to reproduce very quickly, but the thing that always comes into play is that worms do not have a very long life span. Also worms are self-restricting, which means that once they get to a certain population density they will stop reproducing so that they do not become over populated. Worms will also restrict their population based on the amount of food available and the temperature of the bin. A good rule of thumb is that in an average worm bin, worms will double in population in about 60 days and will stop reproducing when they get to about 2,000 worms per square foot. That may seem like a lot, but remember that red wigglers are very small and like to be close together.

How Worms Eat

Worms have a very small mouth at the front of their body that they use to eat. They can only take in small amounts of food that have been softened. That is why you will often have broken down and rotting food in you worm bin that the worms have not yet gotten to.

The small particles of food are broken down even further in the worm’s gizzard. In the gizzard the worms will have small pieces of sand, limestone or even egg shells that it has eaten. As the food and sand mix in the gizzard the worm contracts muscles that cause the food to be ground together with the grit making it digestible for the worms. This is a great reason to make sure that you have some sort of gritty substance in your bin for the worms to use in their gizzards. Egg shells, lime stone or a small amount of garden soil will work well.

I hope that this gets you started with some basic worm information. Up next we will talk about the different types of worm bins.