Harvesting Worm Castings From Your Vermicomposting Bin The Simple Way

Worm farming is an awesome way to create compost to use on the garden, but harvesting worm castings from your vermicomposting  bin or worm farm can be a bit of a drag. I used to struggle with separating the worms from the compost, but no more.

Choosing a good method to separate the worms from the worm compost makes composting with worms a lot less stressful.

I found an awesome video that shows how to do this in an uber effective way, and I wanted to share the information with you.

Whether you have a huge worm farm, or a smaller one, the principles are similar, although you may have to downsize some of your containers

red wrigglers after harvesting worm castings

If you are doing this after a few months of worm farming, you'll see that almost all of the food scraps have been broken down into a rich compost due to the action of the worms.

Preparations For Separating Your Worms From Compost

When preparing to harvest your worm compost, it's important to withdraw feeding to the worms for 2-3 days before the harvesting date. This prevents the worms from all coming to the surface. They tend to dive down deeper into the bin in search of food. At least, this is the case for worms like night crawlers. Red wrigglers tend to dwell close to the surface, so you definitely need to follow these steps to harvest your worm compost effectively if red wrigglers are your worm of choice.

You'll still be removing some worms as you shovel the  finished worm castings out of the vermicompost bin, but nothing like if you had just fed them and they had all come to the surface to feed.

Next, get your large plastic bin and shovel ready to remove the worm compost from the main farm.

The Vermicompost Harvesting Method

1. Begin by using the shovel to remove the compost, layer by layer from the worm farm, and place it into the storage bin. As you get closer to the liner (if you are using one) switch over to the small hand scoop to continue removing the compost.

As I mentioned, many of the worms may be living much deeper in the bin or vessel. You can leave those and just harvest the relatively sparsely populated worm castings. I hate killing worms, chopping them up with a shovel, so if I can, I leave the bulk of them in peace!

2. Once your storage container is full of the castings, use the hand rake to level out the surface and leave to rest for 10-15 minutes.

As mentioned in the video, the red wrigglers will burrow deeper into the compost, and you can then carefully scrape the top layers of the worm compost off, and place it on one of your container lids.

They won't burrow too deep, so scooping just a few inches off the top, sprinkling it onto the plastic lid. You'll start to see worms appearing on the surface of your plastic container again.

3. Agitate the surface with the hand rake and wait another 5-10 minutes as the worms disappear beneath the surface again. Time for a cup of tea while the worms attempt to avoid the light.

4. After the cuppa, and while you wait for the worms to disappear beneath the surface, you can sift the vermicompost into the 15 gallon feed pan or another suitable container using a compost sieve, removing larger pieces of debris from the sieve.

You can choose to make your own, or purchase on on Amazon, where there are plenty to choose from, and most are really low cost.

5. Place the larger particles and any straggler worms into another container, and you are left with the gardener's 'black gold', an incredible, rich and light humus that you then use to feed your plants.

Red wriggler compost worm

Compost worms escape the light during harvesting

6. Go back to the storage container with the bulk of your compost still awaiting processing, and repeat the process. Although the process seems drawn out, it's actually quite quick, depending of course on how big your worm farm is. Continue this process until you have removed most of the compost from the container and sifted it. You'll be left with a think layer of compost in the tub, with almost all your worms in that layer.

7. Transfer the castings into feed sacks using the plastic kitchen bin with the bottom cut out. You can then store the worm castings until you need them. The waste bin is a great idea as it holds the bag open while you fill it. I love this idea and am implementing it for my own worm farming system.

8. Add some coconut coir back into a container as a bedding for your worms. Rehydrate in a wheelbarrow or appropriate container. Make sure your coconut coir is suitable for vermicomposting, this one looks like the perfect product.

Make sure the coir is well hydrated and them break it up, and add to the bin where the worms are going to be housed temporarily.

9. Once you have completed this process and removed all the compost from your worm bin, separated the worms, bagged the compost, you are ready to re-introduce your worms to their normal home.

10. Add the remainder of the coir to the bottom of the worm tank, combine all your worms into one container, wait 5 minutes, scrape the last of the compost from the surface and you're done. Place all the worms into their home and add some fresh kitchen scraps.

11. Cover the worm farm and rejoice in a job well done. Wash up, put the kettle on and enjoy another cup of tea, you deserve it.

12. Check out this article on how to use worm castings once you've harvested them.

Tips For Speeding Up The Process

Ideally, you should be harvesting your worm castings in bright sunlight, it will make the worms burrow down quickly to avoid the light.

If it's dull, or lighting is poor, using a Snap On LED light is a great idea. The worms hate the light and will burrow quickly. In fact, I'd recommend this for any occasion where there isn't bright sunlight, it will save you a lot of time.

View The Snap On 2000 Lumens LED Light On Amazon

Harvesting Worm Castings Video

Hope you got a load of value from this video and short guide.

Happy Worm Farming

More Useful Composting Articles:

How To Get Started Trench Composting

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