How Many Worms Can One Bin Hold?

The conventional wisdom in the area of how many worms can one fit in a worm bin hints that you may have one pound of worms for every one square foot of surface area. A typical rubber maid tote is approximately 30x20 which would be 600 square inches. Divide that by 144 (one square foot in inches)and you get 4.16 square feet of surface area.

Following the formula- you may have 4-5 pounds of worms.

If you are buying worms- conventional wisdom would also say to start out with half your capacity and allow the worms to grow into your bin. In other words- don't calculate your maximum amount and purchase that amount, but buy half and with the space available and adequate food supply, the worms will feel free to follow their biological tendencies and start filling the bin themselves.

When it is time to harvest the castings (approximately in three months) the worms should be nearing their maximum density and you can separate them into two containers.

I have also heard numbers for different species for volume (cubic feet) of space they need. We'll cover that in another post.