Vermicomposting at Home!
I compost using a lot of different methods, but I genuinely think that the method of composting most suited for home food scraps is vermicomposting.
Vermicomposting is where you use worms to expedite the breakdown of your food scraps. It has a lot of benefits to the home composter: worms break down the scraps surprisingly fast, you don't need to follow a careful composting recipe of food waste to garden scraps, and worms have a gut full of wonderful microorganisms that make the worm castings (worm poop) a super beneficial addition to your garden.
In this blog, I am going to show you how I built my flow-through worm bin and give you tips and tricks on having a successful vermicomposting operation at your home.
How to Build a Flow-Through Vermicomposting Bin:
It's fairly simple. Build a raised box, leave gaps in the flooring to harvest the castings, fill it with dirt or soil, add a happy family of a few hundred Red Wiggler Worms (try Uncle Jim's Worm Farm), and sprinkle a thin layer of chopped food scraps every few days to feed the worms.
Step 1: Build a raised box with no bottom.
Use whatever wood you have around. I used reclaimed pallet wood which you can find plenty on Craigslist from businesses needing to get rid of them. If you choose to purchase wood, it wan be fence post wood as it is not holding much weight so the pieces can be fairly thin.
The important thing here is to give the worms some depth (the like to crawl under the soil to get away from the light), and some width so they have space to roam and munch. I made mine about 40" long, 15" wide, and 13" deep.
Make sure to give your raised bed some legs to stand on. In the flow-through system, you take the worm castings off the bottom and feed the worms from the top, so you need to be able to reach under the bin.
Step 2: Put either slender wood slats or PVC pipe as the base to the box.
I used PVC pipe that I was able to reuse, but if you'd rather use wood that would be fine too. Make sure to leave at least 2 inches between each slat in the base to be able to reach in and get decent handful of castings from each row.
How I built this was I got 1/4" PVC pipe, drilled 1/4" holes halfway through the 2x4's along the base of the box, and just slid the PVC pipe into it. I have seen other worm boxes where people drill all the way through their base wood, which is fine too you'd just need longer PVC pipe and a stopper on each end to prevent them from being pushed out.
Step 3: Prep the environment for your new worm friends!
In your empty box, you'll see that there are a bunch of 2 inch gaps on the base. Line the bottom with brown paper grocery bags or another sturdy paper. Around the time your first worm castings will be ready to harvest (after about a month with the worms), these paper bags will be decomposing or at least moist enough to easy rip apart to get to your castings.
Put a bunch of extra garden soil into the bin, fill it 80% of the way to the top, and add your worms! Water the soil a bit, worms like it moist, but don't want to drown. They will thrive at about 60% moisture...which means if you take a handful of soil and squeeze, the soil will clump up into a ball but not let any water drip out (maybe one drop if you are really strong).
Step 4: You are ready to recycle those kitchen scraps!
Worms can handle a thin layer of vegetative food waste mixed slightly with the very top layer of soil. They don't like to be overfed for whatever reason, so some households make 2 worm bins to alternate feedings if they are constantly producing a good amount of food scraps. Feeding them about every 3 days should keep the flies down and be a good cadence for the worms digestion.
Some tips on how to do this successfully:
- Chop your kitchen scraps before feeding them to the worms. This way, they will get broken down faster and you can feed more regularly.
- Keep your worms moist! Worms are like every living thing, they need food and water to survive. They will dry out and die if you let the soil to dry out, so make it a little ritual to go out with your coffee in the mornings or after work to check on their moisture level and say hi. It should be wet enough for the soil to clump together in your hand, but not have any drops of liquid come out if you squeeze.
- Keep your worm bin in the shade! Worms like the darkness, they are underground critters after all. They will bury themselves deep if they are in a sunny spot, and you want them to come closer to the surface to eat your food scraps, so shade is key! I experimented once with putting a lid with air gaps over my bin to let them have lots of darkness all day, but that attracted fruit flies quick, so shade is the way!
- If you do have a larger food scrap load one day and you are getting flies or smells, cover the whole surface with shredded paper (without colored ink). This will become good vermicompost too, but can keep smells and flies down for a week or so after putting it on. This is what it will look like:
- Get to know your worms and their taste buds! Worms actively do not like any sort of citrus or onions. They won't eat meat, dairy, or bones either, nor do they like an overly acidic environment, so having too many coffee grounds compared to other food items will not be good for them. Also, stay away from anything too fragrant like eucalyptus leaves. They LOVE vegetable and fruit scraps! Vermicomposting has more restrictions on what you can feed the worms, but the castings will do wonders for your garden :)
Step 5: Harvest your Worm Castings!
After at least a month of letting the worms digest and hang out with their hundreds of friends, you can start taking some castings off the bottom. The first time, just reach underneath the bin and rip the remainder of the paper bag out, and take a handful of castings from between the PVC pipes or wood slats. This stuff is RICH with microorganisms, so make sure to put it immediately in your garden or potted plants. You can just apply it right to the top of the soil and water, and you will have living healthy soil in no time!
Do note that worms decompose food scraps at a low temperature, so some pathogens may not be killed and seeds may still spout. I got some really healthy cucumber spouts from my worm bin the other day, and just replanted them so I should have cucumbers in a few months! But just know this stuff may happen and it's all good.
Happy worm composting, friends!! :)