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How Many Worms is Needed to Start a Worm Farm?

According to experts, there are numerous factors that will influence the number of worms you need to start a worm farm.

Howbeit, you will need at least one pound of worms per square feet of the bin being used to start, or better still, one pound of worms per pound of food waste. There are around 1000 mature worms in a pound, but still the amount you need will vary depending on certain factors.

Worm farms use earthworms to break down organic matters like food scraps to produce worm castings and the liquid ‘worm wee’, primarily referred to as worm casting leachate. Although every type of earthworm can perform this task, however some breeds can do it faster and better than others.

The earthworms used in worm farms are compost worms and are quite different from the regular earthworms seen in garden soil. Note that compost worms are surface feeders and do not always burrow deep into the soil like garden earthworms.

The numerous breeds of compost worms such as Tigers, Reds, and Blues are well renowned for eating their own body weight in food each day, meaning that a pound of worms will expend that same equivalent of food daily. Meanwhile, normal garden earthworms only eat around half their body weight each day, and this means they are not ideal for composting.

Also have it in mind that compost worms won’t survive in normal garden soil because they are surface feeders and won’t burrow deeply into the ground to the cooler soil in the heat of summer like normal garden earthworms. They also need thick layers of composting organic material on top of the soil to feed on, and if there’s no organic matter on top of your soil that is breaking down, then those worms won’t have any food.

All earthworms are part of an ecological class of organisms referred to as decomposers; they digest rotting organic material and convert them into worm castings. Also, since they don’t have any teeth, earthworms always have to wait for their food to start breaking down before they can start to consume it.

Howbeit, if their food is chopped up or broken up, it breaks down faster, and the worms can eat it sooner. When starting a worm farm, it is vital to get the right number of worms to avoid overfeeding them or not having enough food for them to eat.

Also, have it in mind that red wigglers can easily regulate their population to align well with the environment they are in. If there is less food in the compost bin or limited space, they tend to either slow down their reproduction or maintain their population level, or the adult worms will begin to die off to make room for the babies.

Factors That Influence the Number of Worms Needed to Start a Worm Farm

Worm farms are more or less worm composting systems, or more correctly, vermicomposting systems, and earthworms are one of the fastest composters there are. However, deciding the number of worms you need will depend on certain factors, and they include;

  1. Size Of Bin

There are various bin sizes you can use to start your worm farm. You can create a bathtub worm farm with a capacity of around 200L, which is a fair bit of space! You can also make a wheelie-bin worm farm with a capacity of 140L, 240L, or 360L that takes up very little space on the ground.

However, note that the type of bin you choose will influence the number of worms you need. Just like it was stated above, a good rule of thumb for determining how many you need is one pound of worms per square foot of surface area. However, there are two critical caveats to this traditional approach to calculating need.

First, have it in mind that red wigglers can multiply quickly in a healthy environment. Therefore, if you size the population to the size of the bin then you have to be ready to regularly transplant some of them to another bin so that you do not overpopulate the bin.

Secondly, you will also have to make sure that you can supply a consistent amount of food to meet their daily feeding requirements. Five pounds of worms for a huge bin seems ideal until you realize that you cannot steadily provide substantial food scraps to feed them.

  1. Quantity Of Food Waste

This is another factor that will influence the number of worms you need to start your worm farm. Note that you can decide the amount of worm you need based on the number of food scraps that are steadily available, and according to experts, this is generally a more sound approach.

Have it mind that red wigglers can consume about half their weight of food each day, and if you have one pound of worms, you have to ensure you provide them with around one-half pound of food scraps every day, although it doesn’t have to be exact but this is a good rule of thumb.

Just like it was stated above, there are about 1,000 mature composting worms in one pound, so if you can steadily provide four pounds of food waste, then you need at least two pounds or 2,000 worms. However, to know the amount of food waste a household goes through; collect all of your food scraps for one week and then weigh it.

According to experts, one to two-person family will more or less produce about four pounds of food waste in a given week while a larger family will produce up to six and a half pounds of food waste. You only have to make sure that you have a bin adequate enough to accommodate the worms purchased along with room for them to populate.


Note that the amount of worm you need will however depend on how big your bin is and how many food items you plan to compost. However, it is always advisable that you start small with 500 worms or less, learning how to maintain a healthy bin and their feeding habits, and grow from there.

Unless you intend to venture into commercial vermicomposting, there might be no need to turn a fun project into a stressful event.