How to Make a Worm Farm

How to Make a Worm Farm

November 24, 2018

There are many things that can offer subtle assistance to make our lives healthier and our planet stronger.  Composting and green homes are one, but let’s not forget the humble earthworm, the superheros down under.

A worm farm significantly accelerates your compost breakdown and are great beneficial workers for your garden soil.

There are some extra responsibilities you need to factor in to keep your worms happy and healthy. The biggest of these factors is temperature. Compost can get pretty hot if it’s not aired correctly. Too much heat will cause your worm population to flee for their lives. There are also some important scraps not to add to keep your worms happy. I’ll cover that later on in the post.

Overall worm farms are easy and effective waste transformers and are great fun for all ages. You can get this particular worm farm going from scratch in less then an hour.

After my previous post about composting a couple of people mentioned they were surprised at how expensive compost bins were, given that basically, they are just plastic drums. Which is a fair comment, but nevertheless it’s a worthy investment, especially as the materials need to be hardy enough to cope with some pretty severe weather conditions. So, in saying that I thought I’d create this post with a Do It Yourself version, after all, I cover cost saving DIY projects around the home frequently, so it’s probably time your green garden options got the same helpful treatment.

As well as keeping your worm farm start-up costs down, you also get to reuse items, which adds to the reducing waste and lowering our impact on the environment.

Buying worms

Weirdly, worms can be purchased online and can live for up to five days in transport, so factor in the postage distance and things like weekend delays before you hit the BUY button. You can also buy worms locally from your nursery. A bag of about 1,000 is a good number to start out with.

What you get

You can make a simple worm farm with just one box, however, you can also stack two identical sized boxes on top of each other to make a deluxe version (or sit a smaller box inside a slightly larger one. Your worms will go in the top box with the runoff liquid falling into the second, empty box below. You can tip the run off liquid into the garden from time to time to enrich the soil, as an extra bonus fertilizer. You will need to add more water to dilute the liquid (known as worm tea) first, as it’s very potent. Use 1 part worm tea to 10 parts water.


• 1 or 2 tote boxes - preferably made of rubber or plastic (to endure the weather).

Any box you have on hand will do, although for deluxe double boxes they need to be the same size so they can comfortably stack. Try for around a 30-litre box, approximately 38cm wide, 64 cm long and 13 cm high.

You can also ask at your greengrocer if they have polystyrene boxes you can take. A lid that fits is a great bonus if it’s available, you only need one lid, even if you use two boxes. If there is no lid for your free box you will need to make one up using a cut piece of cardboard or polystyrene.

• A drill to make air holes in the box (use a medium sized drill bit).

If using polystyrene boxes then a pencil, screwdriver or knitting needle will work well.

• Newspaper torn into pieces or fine screening sheets.

• A 600gr packet of bedding material (peat moss).

• A bucket or container to hold enough water to soak your peat moss.

• A hessian bag or hessian material piece.

• Composting worms (about 1,000 will be good to start with).

Building your worm farm

1. In the bottom of one box make 10 - 20 evenly spaced holes for drainage. Add some additional holes around the top of the box, just under where the lid will sit for air ventilation. This will be your worm box.

2. Place the newspaper pieces in a container or bucket and fill with water.

3. Stick the wet newspaper pieces over the bottom of the box as a lining. Keep some wet newspaper aside for later.

4. Soak the peat moss in the same bucket of water (no need to change the water first) and allow it to expand.

5. When ready, place the peat moss in the worm box, about 5cm deep. It doesn’t need to be overly wet, squeeze out any excess water as you transfer it to the worm box.

6. Gently add some composting worms (red wrigglers). They will move down into the soil within a few minutes if exposed to light (sunlight or artificial light).

7. Cover the soil over with the remaining wet newspaper pieces.

8. Set the lid on top or rest a large piece of cardboard or polystyrene over it as a lid. If you are using the deluxe version, stack the boxes so the worm box sits on top of the second box. If you only use one box be careful where you place it as the run off may stain surfaces.

9. Place your worm farm in a shady spot and loosely cover it with a hessian bag or material.

Caring for your worms

Wait a few days for your worms to get settled in before you add any scraps of food.

Best food for worms are eggshells, you can crush them up a little but be careful not to inhale any dust that comes up. Fruit and vegetable peelings and cores, stale bread, coffee grits. Your worms will appreciate you chopping the pieces up so they are easier to get into. You can also blend your food scraps in a processer to help break down the food and add more moisture to the mix.

Never add meat, fish, bones, dairy, onion, garlic or beetroot.

Begin by adding small amounts of food in a good variety to help your worms get used to their new home. You will need to include some additional peat moss or bits of box cardboard and shredded newspaper to the mix as you take out the original soil.

The worms will live in the top 7cm or so of compost and keep moving up as you add more scraps. That allows you to take the bottom half of the compost out to put on your garden and return the younger compost and the worms to the bottom of the box.

That makes for happy worms, a happy garden, a happy planet and a happy you!


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