Worm Composting Takes the
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Worm composting, or vermicomposting is an excellent way to create compost. Red wiggler worms (Eisenia fetida) are kept in a container and fed the same waste you would use in a compost pile. The worms digest the vegetable waste and leave nutrient rich castings, or compost.
Probably the most popular and famous manual on vermicomposting is Worms Eat My Garbage: How to setup & maintain a vermicomposting system by Mary Applhoff. The book is a simple, easy to follow how to of worm composting.
The video below comes from
redwormcomposting.com
, a great resource for worm composting.
How to Build a Worm Bin
Bins can be built of plywood, but will eventually break down. Plastic is quick, cheap, and easy, but can cause water logging. In any event, drill holes in the bottom of your container for liquids to drain. Drill holes in the sides and top for air circulation. Start with a 10 gallon container so as not to overcrowd the worms. It also gives enough room so if there is something in there they do not like, they can get away.
What Do Composting Worms Need?
Your red wiggler companions need darkness, bedding, food, moderate temperatures.
- Worms do not like light. Keep them in complete darkness or they will escape their bin to get away. Also avoid opening the bin frequently and poking around to see what the worms are up to. The light very much disturbs them.
- Worms need roughage, which translates to bedding. Ripped up newspaper, cardboard, straw, leaves or other high carbon content material is what we are looking for. The worms actually eat this as it decomposes, and it also serves to absorb excess moisture.
- Food is your kitchen scraps and other green matter. The same rules apply as to compost piles. No meats or oils, as they will become rancid and nasty. The worms don't like them anyway.
- Worms need moderately warm temperatures to survive and thrive. They definitely cannot survive a freeze. And temperatures above 85F aren't good for them either. That's why a lot of people keep worm bins indoors. However, you can successfully keep them outdoors. Be sure to keep them covered and in the shade.
Setting Up a Worm Bin
Into your bin, place a some bedding. Many people recommend soaking this beforehand, or you can wet it down after everything is mixed.
Place a little garden soil for microbe activity and grit for the worms.
Add some food and cover with bedding. Every time you add food, be sure to bury and cover with bedding. If you don't, you'll end up with dreaded fruit flies.
It's best to let this sit for a week or so before adding worms.
Feeding Composting Worms
Feed your worms as needed. Continue to add bedding. If it gets really wet in the bin, add even more bedding. This is the mistake I made my first time around. It got way too wet in the bin and killed the worms. Just add bedding. You really can't have too much.Be sure not to overfeed. How do you know? Well, at first, you really don't. But know it's better to err on the side of underfeeding.
Dig around in the worm bin. Is there any goopy stuff in there? Any recognizable food? Worms clumped up in areas? These are signs that there is still food in the bin. Wait a while before adding more.
I like to store my worm food in a separate rubbermaid bin. I call this pre-compost because the food starts to decompose in the bin before it gets to the worms. This speeds up the process inside the worm bin. It also helps control overfeeding.
Harvesting Worm Compost
Once the compost starts piling up, help the process along by turning it. I know I promised no turning, but this is easy. In plastic bins especially, the bottom tends to lack oxygen and turn into a layer of goop. Turn the goop so it can finish turning into compost. You may find undigested food down there.The worms prefer to stay near the top of the bin, so turning ensures everything gets composted. Add more paper. As the harvest time nears, add more paper and withold food.
Light Harvest Method
Some people pile the worm compost in small piles and shine a light on it. As mentioned earlier, the worms do not like the light and will try to escape it. They do this by moving to the bottom or side of the pile. You can then separate the worms from compost.
Worm Trap Method
Another method is to fill a sock with food and poke small holes in it. Bury this in the bin. The worms will enter the sock to feed and you can remove the sock and them, leaving the compost behind. I use a potato bag or a citrus bag for this. You will need to do this several times to get most of the worms out.
Migration Method
Yet another method is to place a fresh bin, with fresh bedding and food on top of the ready to harvest bin. The top bin will need large holes in the bottom, at least 1/2".
Just make sure the bottom of the new bin is in contact with the compost surface of the old bin. Feed the top bin only and the worms will migrate to the new bin. This is how the commercial worm bins work.
All of these methods will leave worms behind. You can try to screen leftovers out with a 1/4" screen. Just gently push the compost through the screen. This is difficult to do when the compost is wet. Read on about finishing compost.
After you harvest your worm compost and worms. Start a new bin!
Finishing Worm Compost
It's perfectly fine to use the worm compost straight out of the bin, as it is, leftover worms and all. Or you may prefer to finish off the compost.The fresh from the bin compost will be very wet. You can move it to an empty bin with holes or vents and let it sit for a while.
It will continue to compost further.
Any eggs will hatch and more worms will appear. I grab these guys as they crawl up the sides of the bin and put them in active bins. Some worms stay in the compost and continue to work.
After a period of time, this compost will be drier and more homogeneous.
Now, you may want to screen the vermicompost. Use a 1/4" screen for worm compost, and 1/8" for more pure castings. Screening will also help remove any worms that are left in the compost.
For more hands on with worm composting, check out the worm blog.
Return from worm composting to composting
