How to compost with worms: vermiculture

Composting is great. It’s a fairly simple and easy part of a sustainable lifestyle: It cuts down on your landfill contributions, creates usable nutrients for growing plants, and as I’ve been learning recently, you can do it while you play with worms.

I’m working with an organization called YEA Corps this summer. YEA does youth programming with the Minnesota Internship Center, an alternative high school in the twin cities. The high school kids work with an aquaponics system (if you don’t know what that is, you really must check it out, it’s awesome — I’ll have to post about it soon), grow mushrooms in buckets, and manage the vermiculture set-up.

Part of my internship involves taking over the vermiculture project for the summer: I’m evaluating the systems in place, improving them in any way possible, and writing guidelines so the project can be replicated as YEA Corps implements more programs.

So a plus of this whole thing, among several, is that I’m learning about how to create a compost that works well inside throughout the harsh Minnesota winter. (Season extension! Permaculture!) And I’d love to share it with you.

Basically, you take a bin.

Drill a hole into the side of the bin, at the bottom, so that you can drain the worm juice into plastic containers (pictured right). This will keep the bin from getting too wet, and produces an extremely concentrated liquid fertilizer.

Put about 4 inches of peat moss, shredded coconut hulls, finished compost, or coffee grounds on the bottom of the bin. If the material seems too dry, add water to dampen it.

Over this bottom layer add a cupful of fine sand.

Now come the worms. Add your worms — these will be red wriggler worms, available at a variety of places, including the Recycling Association of Minnesota, Laverme’s Worms (they actually sell whole kits), Uncle Jim’s Worm Farm (not local, but a priceless name), and of course, craigslist.

On top of the worms sprinkle a handful of sand, and then a handful of crushed or ground-up eggshells.

After that, add a couple of inches of bedding. Possibilities include dry leaves, sphagnum moss, wood shavings, and unbleached paper towels.

And cover everything with black plastic sheeting. See below.

And there you go! A worm composting bin that will yield you high-nutrient compost year-round.

Now: a few maintenance tips.

  1. The ideal temperature of the bin is 45 to 60 degrees Farenheit.
  2. Always bury uncomposted food (the stuff you are adding) under a couple of inches of the “compost matrix” (worms + compost).
  3. Leave the plastic jugs with worm juice uncovered. Continual exposure to the air will keep it from smelling bad.

Good & Bad Worm Food

Good worm food is fruits, vegetables, fruit and vegetable peelings and cores, crushed up eggshells (they provide calcium which enhances the nutrient content of the compost), and any meat that hasn’t been left out.

Bad worm food is meat that’s been sitting out in the open air, white flour, fried foods, processed foods, any food with a lot of preservatives, and most non-water liquids.

How to Get & Use Your Compost

The compost that a vermiculture system produces is extremely dense and fertile. It looks and feels like mud, collects continually along the sides and at the bottom of the bin, and can be harvested whenever it’s found.

Most vegetables will grow well in high-nutrient soil, but not all. Be careful not to use too much vermicompost — it should usually be mixed with soil.

To harvest a larger amount of compost, stop feeding half the bin for a month. Then scoop out the unfed side for your use, push the fed side onto the emptier side, and re-cover everything with bedding and plastic sheeting.

Worm juice (the stuff that collects in the plastic jugs) is also super concentrated. To use it as fertilizer, dilute it 20 parts water to 1 part worm juice.

So there you have it! An awesome way to compost, inside, all year if you want to. A way to help you grow more food that doesn’t take up too much space or too much time. Permaculture at its finest… vermiculture.


About PRI Cold Climate

PRI Cold Climate is an organization centered in Minneapolis that promotes permaculture throughout the region, fostering sustainable lifestyles and communities. We design and demonstrate permaculture systems specific to colder climates like ours, and provide leadership and resources for the permaculture community.
This entry was posted in Uncategorized and tagged , , , . Bookmark the permalink.

One Response to How to compost with worms: vermiculture

  1. autumnworm says:

    Great article… You feed your worms meat that is not left out? What does that mean?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s