From 1,000 to 1 Billion Worms

From 1,000 to 1 Billion Worms

People sometimes ask me "Captain Matt, how many worms should I buy?" or "How long until I can grow my herd to ________ ?" My most frequent answer of how many worms to start with is 1,000.

Unless you're really good at math, it's best not to try figuring out how many worms you'll have from your initial herd reproducing beyond 6 months out. The numbers can get really big and your family might get really scared of being overrun by worms! It's also highly dependent on quite a few factors. All estimates are approximations, but are very useful calculations.

Population Growth

Let's say you have 1,000 mature worms that are ready to breed...

For simplicity's sake let's approximate a worm breeding cycle at 1 month. In proper breeding conditions (temperature, moisture, oxygen, food) each worm could produce 4 cocoons in that month, but let's estimate on the low end at 2.

Each cocoon will contain at least one, but sometimes 5 or more baby worms! Again, let's use a low end estimate of 2. Here's how your worm breeding timeline could play out.

Month 1

At the end of one month, your 1,000 worms could produce 2,000 cocoons and 4,000 baby worms, bringing your herd up to a total of 5,000! Now... it does take 3-4 months for a red wiggler to mature - so those babies won't start reproducing right away.

Month 2

At the end of month two, your 1,000 worms could still just produce 2,000 cocoons and 4,000 baby worms, but those new 4,000 baby worms get added to the 4,000 from month one, bringing your herd to a total of 9,000!

Month 3

At the end of month three, your 1,000 worms could still just produce 2,000 cocoons and 4,000 baby worms, but those new 4,000 baby worms get added to the 8,000 from month one and two, and your herd is at an impressive 13,000 head (or is it tail?) count.

Month 4

This is where things start to get exciting... remember those 4,000 baby worms from the first month? They are now full-grown and ready to mate and reproduce. This month those 4,000 month one worms get added to your 1,000 original mature worms for a total breeding population of 5,000. Those 5,000 can produce 10,000 cocoons resulting in 20,000 new baby worms.

Big Numbers Milestones

Take this calculation out further and you'll start hitting some really large numbers.

  • Month 8: 100,000
  • Month 12: 1,000,000
  • Month 23: 1,000,000,000 (at this point space would be a problem - as this is more worms than most large-scale worm farms in the world produces)


If you or someone in your family is good at spreadsheets, make a table with formulas for the calculations for 24 months. The math (and growth potential) is truly mind boggling!!!

Whether you're interested raising worms for gardening, fishing, or even a side business, the sooner you start, the better - as herd growth starts slow and then ramps up after a few months. That's actually a good thing, so you can learn lessons and make mistakes early on that don't cost as much time or money.

I wish you success in your worm goals!