When you want compost outdoors, a very inexpensive bin can be made from wood pallets. These large wooden rectangles easy to find at local stores, warehouses and any business that receives shipments by truck. Reusing pallets reduces waste and saves money. All you need is a little elbow grease, a few tools, and some inexpensive supplies. When your composter is finished, you can start a productive composting program. Adding composting worms makes the composting process go faster. Soon, you will have free compost to help your garden and lawn grow.
To start, find a location for your worm bin. Put it a short distance from the house, not too close to a seating or play area. You will be walking out there frequently to deposit kitchen scraps. Placing it under trees or shelter is a good idea because too much moisture can drown composting worms.
- 4 or 5 wood pallets. Avoid pressure-treated, which can be toxic. Look for pallets with the smallest amount of space between the slats.
- Screw gun
- 8 L-brackets
- Thick zip ties, 26″ to 36″
- A handful of 2″ long wood screws
- Optional: 2 sturdy hinges; hook and eye latch for door
- Optional: Large flexible plastic-backed mat or other cover for the bin
- Optional: garden netting
To make the bin:
- Place one palette on the ground in the exact location of your bin. This will be the base. (Now is a good time to make sure your other pallets will fit as walls around the base. Experiment a bit to make sure this everything will fit together before proceeding.)
- The “front” of the bin will face into your yard, so you can easily access it. This will be a swinging door you can open and close.
- Stand up the back panel and attach it to the base. Use the screw gun to fasten 2 L-brackets to the base. Note: you can use zip ties, but the bin might not be sturdy if you cut corners on this step).
- Attach a side panel to the base using 2 L-brackets. Then, lash it to the back panel using zip ties. Pull each zip tie taught, and trim excess with scissors.
- Repeat for the other side. You now have a 3-sided structure.
- Optional: If you want to add a door, you will be able to build up the pile larger inside the composter. If you decide to make a door, place the 5th pallet over the front opening. Attach 2 hinges to the final pallet, and screw the hinges to one of the sides. Test the door to make sure it opens out easily. Screw in the hook and eye so the door can be locked and unlocked easily.
- Optional: Place a covering over the top of the entire bin. Having a cover will cut down on moisture in the bin, which causes odors and can harm the worms. Either make one out of wood or plastic, or use a large welcome mat, or whatever you can find. You might want to attach the cover to the sides of the bin so it doesn’t blow off. Make sure you can lift off the cover when you want to access the bin.
- Optional: You can help prevent organic matter from sliding out between the slats by using garden netting. Wrap the netting around the outside of the bin and staple it in place. Be sure to leave a gap in the netting, so the door can still swing open.
Now you can set up your pallet composting bin. You will need bedding for the worms to live in. This material needs to have a neutral pH, retain moisture, allow the flow of oxygen, and not irritate the worms’ skin. Here are some ideas: shredded brown cardboard, paper (unbleached), or newspaper (black ink only); aged compost; aged manure from cows or horses; coconut coir; pure peat moss (no added ingredients); hay; straw; and/or wood chips. You can also use autumn leaves.
Lightly moisten the bedding as you add it, using a watering can. Stir. You don’t want it to be wet; it should have the consistency of a wrung out sponge.
Now add composting worms. These come in bags from places like Uncle Jim’s Worm Farm. Worms from bait shops are not usually the right type for composting. Uncle Jim recommends Red Worms for composting. The larger Super Reds (European Night Crawlers) can be used for composting, but they are better for releasing into the lawn or garden for aeration and fertilizing. Gently pour the bag on the top of the compost pile. No need to separate them – and don’t bury them. Let them dig down and find their own way into the bedding.
Your last step in setting up the pallet composter is to add organic matter. You can use kitchen scraps, coffee grounds, and garden waste. Bury the material to discourage pests, or just chuck it on top. Either way, the worms will find it and start breaking it down. In a few months, you will have free compost you can harvest. This rich finished fertilizer is all-natural and perfect for making plants grow.
Note: Pallet composters can be extended to make 2 or 3 bins. Share walls to save space. Multiple bins are great for larger-scale operations such as an apartment building or large yard. When one bin is full, start on the next bin. By the time you fill the last bin, the first one will be ready to harvest.