Harvesting Vermicompost

Estimated reading time: 3 minutes



Getting your worm container ready

The size of your bin, your number of worms, and the conditions of your container will dictate when it’s ready to start harvesting the vermicompost. Worm castings (worm poop) can help add vital nutrients and bacteria back into the soil. The vitamins and nutrients have been broken down and available to your indoor and garden plants.

To prevent them from drying out, you will want to store your worm castings in an airtight bucket. Worm castings can be tilled into the soil, spread around the base of plants, or made into something called “compost tea.

Harvesting vermicompost from a single bin

Over time, your bin will start to fill up. Stop feeding for five to six weeks as you start running out of space. This gives your worms time to break down more bedding and consume all the food in the bin. When your container no longer has remnants of paper or food scraps, you know it’s ready to harvest.

Start your harvest by opening the lid to your bin and even shining extra light directly on the surface of the compost. Light encourages worms to burrow deeper into the container. 

After twenty to thirty minutes of exposing the surface to light, you can harvest the first inch of soil. With a gloved hand or spoon, gently scrape the layer of dirt away. If you start seeing any worms in the compost, stop and shine the light on the surface again. 

Complete this cycle of shining a light on the surface and harvesting the compost. You don’t want to gather all of the compost available. It is good to leave a few inches of the old compost in the bin. 

After you’ve harvested what’s available, add fresh bedding and food for your worms. They will be happy for some fresh food and bedding to start. 

Harvesting vermicompost from a tower bin

The benefit of using a red worm composting container with a tower system is that you can remove a layer of finished compost at the bottom without disturbing worms at the top. 

When you notice a tray no longer has any unfinished bedding or food, you are ready to harvest.

Start by laying a tarp or trash bag on a table. The top layer of compost in your tower system is often the least composted. Gently remove the top layer and place it on the tarp. Use this bin as a place to put any worms you find while sorting your compost. 



Please take the bin below the top bin and flip it over on the tarp or trash bag. You can start harvesting right away or use a light to encourage worms to burrow deeper in the pile. 

With a gloved hand or spoon, gently scoop the first inch of compost. Remove any redworms and cocoons you see from the compost. Return these worms into the top bin that should be on the tarp too.  

Once you’ve cleaned out the middle tray, place the former top try in the middle. Add new bedding and food into the tray you just harvested. Place this tray on the top, and now your worms have room to grow, and you’ve harvested nutrient-rich compost.

Summary Harvesting Vermicompost

I hope today’s blog post has helped you better understand the basics of harvesting vermicompost. There is much more information to help make it even easier and more nutrient-rich. Feel free to share your tips and tricks for harvesting castings in the comments section below.

Happy composting!