Wednesday, November 18, 2009

Composting With Worms

Let worms eat your organic waste! They will happily turn it into some of the best fertilizer on earth – worm compost, otherwise known as “worm castings” or “vermicompost.” A fascinating, fun and easy way to recycle your organic kitchen wastes, vermiculture:
  • Requires very little work
  • Produces no offensive odors
  • Helps plants thrive

Only a few things are needed to make good worm compost: a bin, bedding, worms and worm food. By following the steps listed below, you will learn to make, maintain and use your own worm compost. Only a few things are needed to make goodworm compost: a bin, bedding, worms and worm food.

Worm Bins

Your bin needs to be only 8 to 16 inches deep, since compost worms are surface feeders. You can build your own bin by using a washtub, dish pan, used shipping crate or a commercially available worm bin. Just be sure your bin has a lid to keep out flies and rodents. It also needs holes in the bottom (a quarter inch or smaller), for ventilation and drainage.

The rule of thumb for bin size is two square feet of surface area per person, or one square foot of surface area per pound of food waste per week. Because worms like moderate temperatures, place your bin in a shady location where it will not freeze or overheat.

Bedding Materials

Black and white newspaper is the most readily available and easy-to-use bedding material. Tear it into strips about one inch wide and moisten so it is as damp as a wrung-out sponge. Cow or horse manure can also be used to lighten bedding and absorb excess moisture.

A handful or two of soil, ground limestone or well-crushed eggshells every few months are good for providing grit and calcium. Fill your bin with moistened bedding, toss in a few handfuls of soil, and you are ready to add the worms and food. Over time, the bedding and food are eaten by the worms and turned into dark worm compost.


The best kind of worms for composting are “red worms” or “red wigglers.” They are often found in old compost piles, but are different from the earthworms you would normally find in the ground. These worms have a big appetite, reproduce quickly and thrive in confinement. They can eat more than their own weight in food every day! When purchasing red worms, one pound is all you need to get started.

Feeding Your Worms

Worms like to eat many of the same things we eat, only they aren’t so picky. Some of their favorites include:

  • Stale bread
  • Apple cores
  • Orange peels
  • Lettuce trimmings
  • Coffee grounds
  • Non-greasy leftovers
  • Vegetable scraps

Begin feeding your worms only a little at a time. As they multiply, you can add larger quantities of food waste. Bury the waste into the bedding regularly, rotating around the bin as you go. When you return to the first spot, most of the food you buried there should have been eaten. If not, don’t worry. Just feed the worms less for a while.

After you have been feeding your worms for three to six months, you may notice the bedding has been eaten, and you can begin harvesting the brown, crumbly worm compost. Harvesting the compost and adding fresh bedding at least twice a year is necessary to keep your worms healthy. There are several ways of collecting your finished worm compost.

Method 1: Move the contents of your worm bin to one side, place fresh bedding in the empty space and bury your food waste there for a moth or so. Harvest the other side after the worms have migrated to the new food and bedding.

Method 2: Remove one-third to one-half of the contents of your bin, worms and all, and add the worm compost to your garden soil. Add fresh bedding and food to your bin.

Method 3: Spread a sheet of plastic out under a bright light or in the sun. Dump the contents of the worm box into a number of piles on the sheet. The worms will crawl away from the light into the center of each pile and you can brush away the worm compost on the outside by hand. Soon you will have wriggling piles of worms surrounded by doughnut-shaped piles of worm compost.

Using Your Worm Compost

Worm compost is more concentrated than most other composts because worms are excellent at digesting food wastes and breaking them down into simple plant nutrients. Use it sparingly for best results.

Mulching and Amending Soild

To mulch with worm compost, apply a one-inch layer to the soil around plants. Be sure the worm compost is not piled against plant stems. To amend soil, worm compost can be spread one-half to two inches thick over garden soil and mixed in before planting, or mixed into the bottom of seeding trenches or transplanting holes. You can also mulch your worm compost into:

  1. Houseplants: Sprinkle worm compost around the base of plants to fertilize. Each time you water, plant nutrients will seep into the soil.
  2. Potting Mixes: For healthy seedlings, mix one part worm compost with three parts potting mix or three parts sand and soil combined. Peat moss, pearlite and worm castings are also good ingredients to add.

Warning Signs

Some symptoms that your worm composting is not going as well as it could are:

  • If your worms are dying
  • If your bin smells rotten and/or attracts flies

Worms Dying

If your worms are dying there could be several causes:

  1. It may be that they are not getting enough food, which means you should bury more food into the bedding.
  2. They may be too dry, in which case you should moisten the box until it is slightly damp.
  3. They may be too wet, in which case you should add bedding.
  4. The worms may be too hot, in which case you should put the bin in the shade.
Bin Smells
  1. First, it may be that there is not enough air circulation. In this case, add dry bedding under and over the worms, and do not feed them for two weeks.
  2. Second, there may be non-compostables present such as meat, pet feces or greasy food. These should be removed.
  3. Third, there may be exposed food in the bin. In this case, secure the lid, cover food scraps with bedding, and cover worms and bedding with a sheet of plastic.
by Earth911


Anonymous said...

Hi, I really enjoyed reading you post about the worm has got me thinking for my allotment and I think I will give it a try...Thanks!!!

Phoenix Capital Software said...

wow! absolutely loved this... thanks for such a informative article.

Would love to see more on sustainable agriculture. Anything on polutry?


Rebecca said...

Excellent post! Love your blog, I have given you the best blog award, you can come over to catlovers to get it!

My Caddy SG said...

I've done this before and wish I had your post to read first. My first batch of worms all died because the environment was actually "too clean"- I didn't give them enough food scraps to eat and they "escaped" and dried out.

Georgie said...

Worms help with so much great post!

Ish said...

Dropping by to say Have a Happy Healthy Holidays to you and your family!

malagosfarmfair said...

The Puentespina-owned Malagos Farm practices sustainable farming and you can witness this by visiting us in Davao City during the Malagos Farm Fair on August 7 & 8--Everyone is invited!

Quiet-Environmentalist said...

I bought a single person wormery. Unfortunately the little fellas were not man enough to take the vegetable waste that I produced. One day the seperator between the liquids and the farm collapsed under the weight and the water started to rise. The little worms all drowned. Tip: buy a good quality wormery!

iva said...

We have invited a vermicompost expert for a workshop (for communities) we organized here in our country and as I listen to him, it is surprising to know that worms really do contribute a lot to sustaining our world.

We have provided the communities with their own vermicompost kits, and now have put up their own organic gardens, and are even making a living selling some of the worms (as they multiply fast!).

Great post. Very informative.