Garden of Eatin' / Insects & Worms

Harvesting My Worm Compost

Finished worm compost

Back in October, I added a new tray to my Worm Factory 360 to keep all those ravenous red wigglers well fed. And then… I kinda forgot about them for a while. Blame the wedding… which I use as an excuse for every end-of-year procrastination, including my Christmas gifting, my garden digging, my oil changing, even my tax preparing. And, uh… those are still not done.

But I digress. I finally got around to harvesting my worm compost, and luckily, my hub has been feeding our Wormville every week from the compost pail on our counter. (If you don’t own a pail like thisHarvesting My Worm Compost 1 for your kitchen, I highly recommend it — it beats running out to the vermicomposter every night to unload your scraps.)

Though I added my second tray in October, my first tray has been steaming and stewing since last August when Nature’s Footprint sent me their Worm Factory 360 to test… six busy months of being broken down by thousands of worms working their way through my garbage. All those onion skins, banana peels, and cantaloupe rinds have magically been transformed into rich, black castings.

Collecting worm compost is a pretty straightforward process. It typically takes around three months for your worms to finish a tray (if you don’t forget about it like I did) and you will likely have a second (or maybe a third) tray in the works by the time your first tray is ready. That means your Worm Factory 360 will continue to be a lean, mean, scrap-munching machine, even as you pull off one of your trays.

Remember that new trays are always added on top, so you’ll want to harvest from your bottom tray. Simply remove the lid and any upper trays, and scoop all the castings into a bucket.

A tray of fully processed worm compost

Worm castings

Fully finished compost resembles a fine, crumbly, black peat. You might find newspaper strips or random scraps that haven’t fully composted yet, but that’s fine — they’ll continue to biodegrade. You’ll likely find a few worms along for the ride as well, but they’ll continue to live happy lives in the earth, so no need to move them back into the bin.

Worm compost

(As my bottom tray had long been finished, I didn’t find too many worms still lingering in it — most of them had already migrated to the top tray. But if you see more than a handful of worms in your bottom tray, you’ll want to encourage them to migrate to the other trays first. To do so, remove all your trays except for the bottom tray and set them aside. Then, remove the bottom tray and stack it on top of the other trays. Replace the whole stack on the base with the lid off. The sudden exposure to light and air will force the worms to move downward where it’s dark and moist. After leaving the lid off for a few hours, you can harvest your compost as above.)

With all the trays removed from the base, check the catch-all tray containing the worm ladder. Collect the castings that have accumulated in that tray (I had a fair amount that fell through from the tray above).

Check the catch-all tray for castings and leachate

Drain the tray of any leachate by turning the spigot in front. You can save this leachate and dilute it with water to use as fertilizer for your landscaping plants. (As I’d mentioned in my previous post, leachate is not the same as compost tea and its nutritive value is hit or miss. Remember: If it smells bad, don’t use it.)

Drain the leachate

Place your active tray back on the bin. If it’s almost full, you can take your old (empty) tray and stack that on top, using the same method for adding a new tray. Your active tray now becomes the bottom tray for your worms to finish composting, and your top tray becomes the active tray to which you add more food.

Since my active tray was less than half full, I decided to let the worms go to town for another few weeks before I add a new tray. In went a heaping of kitchen scraps and shredded paper, followed by a couple sheets of moistened newspaper, then the lid.

Add more kitchen scaps and shredded paper to the vermicomposter

As for all the worm compost I’d just harvested, it can be used right away or it can be stored in a non-airtight container. Just make sure the compost never dries out, as you want to keep a damp, favorable environment for those microbes. In ideal conditions, the compost should keep for up to three years.

Finished worm compost

If you want to learn how to set up your vermicomposter, click here for my first post in the series.

This post is brought to you by Nature’s Footprint. Thank you for supporting the sponsors that support Garden Betty.

Linda Ly About Author

I'm a plant lover, passionate road-tripper, and cookbook author whose expert advice and bestselling books have been featured in TIME, Outside, HGTV, and Food & Wine. The No-Waste Vegetable Cookbook is my latest book. Garden Betty is where I write about modern homesteading, farm-to-table cooking, and outdoor adventuring — all that encompass a life well-lived outdoors. After all, the secret to a good life is... Read more »