How many worms needed to start a worm composting bin can be answered with two questions:
-How much worm food/kitchen waste do you have access too?
-What size is your worm bin?
How Much Worm Food Do I Need
You can either estimate your weekly usage or you can weigh your food waste daily for a week and average out your daily food waste.
Unsure as to what food waste you can feed your worms. Check out this blog post: What You Can and Cant Feed Your Composting Worms
Compost worms eat roughly 25-35 percent of their weight per day. This is the consensus among academia research available however some places on the internet state a much higher amount up to 100% of their body weight. Using the information above, 1lb of composting worms will roughly eat 1.75 to 2.45 pounds of food per week.
What Size is My Bin?
The healthy number of composting worms is 1 pounds per square feet of bin surface area (1:1). Okay, by now you are thinking about your days in high school math class, so area is simply width x length. Example: bin is 1.5ft (18 inches) by 2 feet (24 inches) regular storage bin, your surface area is 1.5 x 2 = 3 sq ft. 3lbs of composting worms would be the most you would want to buy.
So the example above of a bin 18 inches by 24 inches, the ideal number of worms is 3lbs and you would need 5.25 lbs to 7.35 lbs of food a week.
If you want to start a bin out with less that's fine, just make sure you enough food for the amount of composting worms you buy and the bin is large enough. The amazing thing about composting worms is once they reach optimal population, the worms will regulate their population. At this time you can keep one bin going, expand to a larger bin or add another bin.
If you have any questions, feel free to email us. We would love to talk about getting your bin populated with the right amount of worms.