How to Make a Worm Bed

Sally Painter
Cultivating earthworms

Make a worm bed for better garden soil and to increase the amount of compost at your disposal. You can also harvest earthworms to put in your garden beds to aerate and enrich the soil. A worm bed is easy to make and maintain with very little effort or materials.

Simple Method for Making a Worm Bed

The easiest way to make a worm bed is to dig a pit, add shredded paper, wet it down, fill it back in with the dirt, add composting food, and worm. You are done. The only problem is the worm may move out, predators will hunt and eat the worms and your effort was wasted. However, you build a secure worm bed that will last for years.

Step One: Decide Location for Worm Bed

Decide where you wish to build the earthworm bed. Most gardeners find it convenient to have the bed in the garden for easy access. If you have an existing compost pile, you may want to locate the pit beside it. Once you've decided on the location, it's time to get started.

Step Two: Measure Your Worm Pit

You will create either a rectangle or square pit for your worm bed. Some people prefer to use an above ground self-contained worm bin, but an in-ground bed offers you the opportunity to expand by simply digging out more earth. A few tips about the depth and size of your worm bed include:

  • A good rule of thumb is to mark off a 3' x 6' area and dig 18" - 36" deep.
  • You can start smaller and shallower if you wish but it doesn't require much effort to dig a deep bed.
  • The deeper the bed, the more worms and compost you'll have.
Gardener Forking A Patch In the Garden

Supplies and tools for the bed include:

  • Worms
  • Landscape spade
  • Shovel
  • Measuring tape
  • 4 stakes
  • String or twine
  • Hammer
  • Tiller
  • Wheelbarrow

Follow these instructions to lay out your bed area:

  1. Drive the first stake in the ground with the hammer.
  2. Use measuring tape to measure 6' perpendicular to the stake.
  3. Drive another stake at the 6' mark.
  4. Measure 3' perpendicular from the second stake.
  5. Drive another stake.
  6. Measure 6' perpendicular to this third stake.
  7. Drive the fourth stake.
  8. Use a laser
  9. Tie string from the first stake to the second stake and so on until you have string tied to each stake.
  10. You now have your worm bed defined and are ready to start digging.

Step Three: Time to Start Digging

You will use the landscape shovel to cut the soil along the perimeter. If you aren't a perfectionist, you can simply start your tiller and begin digging from the center of the pit. Once you have the soil tilled, you can shovel it into a wheelbarrow to refill the pit later.

  1. You may want to remove the clumps of grass.
  2. Return to the pit and continue to till the next layer of soil.
  3. Remove the tilled soil.
  4. Measure the depth of your excavated rectangle. If necessary, continue to till until you're at the desired depth.
Man Digging Hole With Shovel

Step Four: Shore Up Sides of Pit

You'll want to shore up the sides of your worm pit to ensure it doesn't cave in or invasive roots don't overrun your in-ground worm bin. You can use wood boards.

  1. Measure the board lengths you need two 3' long and two 6' long.
  2. Depending on the depth of your pit, you need to include enough boards so the last ones extend at least 2"-3" above the ground so you can later attach a lid.
  3. Screw the boards together as you fit them along the sides of the pit.
  4. Work one row of boards around the perimeter of the pit before moving on to the next row until finished.

Step Five: Line Worm Bed

You want to line the worm bed with landscaping fabric before filling it in to ensure the worms cannot escape. This cloth allows for air and water flow. You'll need landscape fabric to cover the bottom and pit wall sides, construction stapler with staples, and scissors.

  1. Measure the landscaping fabric to ensure you hav enough to over the interior of the pit, bottom and sides.
  2. Cut size needed.
  3. Begin stapling the fabric to the bottom boards.
  4. Smooth out the fabric as you work.
  5. Move to the next boards and staple the fabric all the way around the pit.
  6. Continue to work your way up to the last boards.

Step Six: Materials for Bottom of Worm Bed

Once you've built the walls, you need to cover the bottom of your worm bed with either corrugated cardboard or soaked newspapers.

  1. Set up a tub of water to soak the newspapers and/or cardboard.
  2. Layer the paper and/or cardboard in the bottom of your worm bed.
  3. Add the tilled soil you removed, don't be afraid to add the top layer of grass and other vegetation since the worms will eat it.
  4. Add worms (purchased or harvested).
  5. Add vegetable food scraps, eggshells, coffee grounds (no meats).
Worm Bed Layers

Step Seven: Put a Lid on It

You can create a hinged lid for your worm bed. This will prevent predators from stealing your worms and your worms from meandering away from their bed. Gather these supplies:

  • 1 sheet of plywood
  • Drill with small bit
  • Lid support
  • Piano hinges
  • Electric saw
  • Measuring tape
  • Screwdriver

Follow a few simple instructions to build the lid:

  1. Measure the plywood 3'1" x 6'1" so there will be a slight overlap along the two sides and front. The back of the pit frame will fit snuggly with the piano hinges.
  2. Install the lid support to prevent slamming fingers while closing the lid.
  3. Using the drill, make multiple air holes to allow proper air circulation.
  4. You can also drill a few holes in the exposed above ground boards of the frame.

Using Worms in Raised Garden Beds

You can dig up worms from their bed and transfer them to your raised vegetable beds to assist in improving soil conditions for growing vegetables. Any worms removed from the worm bed will quickly be replaced since the worm population will typically double between every three to six months. In fact, you may decide to start a small cottage business selling worms to bait shops and other gardeners.

Tips for Attracting Earthworms to Your Worm Bed

A few tips can help your worm bed thrive. You can add specific foods that earthworms love to attract more worms and keep them happy. Whenever you add things to the worm bed, you can leave it on top of the soil or bury it about 3" deep to encourage the worms to feast.

  • Earthworms love fruits, such as apple, peaches and melons.
  • Add coffee grounds to your worm bed. Coffee grounds are a favorite of earthworms.
  • Corn meal is a cheap food source that earthworms love! Turn it over in the soil.
  • Keep your worm bed moist. Don't over water. If your worm bed dries out, the worms will die.
  • Worms are often within the first 12" of soil.

Function and Purpose of Earthworms

Worms are a vital for a healthy garden since they aerate the soil by burrowing, eat and break down organic materials to produce worm castings (poo) that enriches the soil. In vermicomposting practices, worm vermicast is the premium byproduct gardeners seek.

Art of Vermicomposting

Vermicomposting establishes a home for worms often using specific worms, such as red wigglers or white worms, to aerate the soil and convert organic matter into compost. The byproduct, vermicompost contains compost and vermicast (worm castings or worm excrement).

Understanding How to Make a Worm Bed

Making a worm bed can be as simple as digging a hole and filling it in. However, if you wish your efforts to be worthwhile, it pays to take a little extra time and effort to build a secured worm bed that will be productive without the threat of predators eating the worms or the worms moving out.

How to Make a Worm Bed