How to Build a Worm Tower
A few years back we put this short video clip up on YouTube with Permaculture Schools Gardening expert Leonie Shanahan talking about her worm tower. Well the idea seems to have caught on as little colourful worm towers are now springing up everywhere in the Permaculture landscape. While filming a segment with Geoff Lawton recently in his “Soils” DVD we saw an interesting variation that was built into a tank garden laden with vegetables. Some people are worried about using PVC pipes and the one we filmed was made of a heavy concrete pipe construction. It was laden with thousands of Compost Worms and the vegetables grown were bursting at the seams with goodness. So how do you do it?
Here’s a basis rundown on how to build your own Worm Tower.
First secure yourself a tank garden. The one we filmed was made of zinc aluminum but any type will suffice. You could make your own from stacked timber sleepers or concrete slabs.
Fill the tank with soil or create your own soil from filling the tank with newspapers, cardboard, garden clippings and alternating the layers with rotted compost or manure. Eventually the whole thing will turn to compost anyway but may take some time. As Geoff Lawton says “If its lived before – it can live again!” That makes good advice for what you can use in your container garden tank.
Find a large 3 to 4 foot pvc or concrete pipe. The wide 12 inch concrete pipes are ideal. PVC is okay but check to see that it is food grade. We don’t want any chemical nasties leaching out.
Bury the tower about half way down in your tank garden. Half of the tower should be sticking out.
Empty a bag of manure into the tower, filling the tower half way up the pipe. Any sort of animal manure is fine. Horse, cattle, sheep or chicken is perfect. Geoff Lawton favours mixing your manures as this gives your system a “high octane” blend that will have your microbes jumping for joy. Good soil bio-diversity is always a good thing!
Introduce your compost worms into the tower. A small bucket of worms can house easily more than 1000 red wrigglers. Do not use normal garden worms as these are usually a different sort of worm that are more solitary creatures and wont do the job that composting worms are able to achieve so well.
Throw in your garden scraps and secure over the pipe a removable container. Worms don’t like the light so give them a comfortable home to live it. You can also throw some shredded moist cardboard into the tower or straw or raked up garden leaves. Worms love to chomp on rotted cardboard. Keep your tower moist but not too wet.
The compost worms will get to work on the manure and come up at nibble on the vegetable scraps. As long as they have a food source left in the tower they will turn the animal manure and vegetable scraps into high quality worm castings and worm juice that the plants will love to eat. They wont escape either unless you stop feeding them. The worm castings will leach out into your tank garden and you will be feeding your plants from the roots up. A beautiful elegant solution to creating sustainable abundance.
Leonie has recently published an inspirational book called “Eat Your Garden.” We had a recent look at it and it features her worm tower in it as well. Check out her website.