How To Build a Worm Tower
- Milton Dixon
Updated – February 2024
Worm towers are DIY vermicomposting bins built into your garden and are just one of many techniques that permaculture designers can use to support the health and production of one’s favorite trees or shrubs. They are especially ideal to place within a plant guild as well.
How to Use
Above is an empty worm tower pictured as it was installed into the ground in the center of a plant guild at Midwest Permaculture in Stelle, IL. We then put in some wet straw for bedding, a handful of red wiggler composting worms, and a day’s worth of kitchen scraps. For the next couple of weeks, we added our daily kitchen scraps until it was full. Thereafter, the contents would slowly sink down as the worms enjoyed their feast, turning scraps into pure worm castings. About once a week there would be enough room to add another day’s worth of kitchen scraps. If someone had 7-towers they could top off one per day.
The beauty of the system? No mess, no fuss, no smell, no slimy buckets, no flies, and no compost juice to drain. Just insert kitchen scraps and walk away. The plants growing around the worm tower love the nutrients. The worms love their new home. We harvest the worm castings once a year in the spring. The only maintenance is to be sure the area stays moist in dry times (can’t let the worms dry out).
Enter your email address to receive access. By signing up, you'll receive occasional email newsletters with valuable permaculture insights and updates on our courses. We respect your privacy and won't send spam. You can unsubscribe at any time.
Winter?
We’ve used the worm tower for many years in our Northern Illinois climate and during the winter months, everything slows down including our worms. But our little friends have made it through each winter by burrowing down below the frost line which is why the tower should be adequately deep and kept full over the winter months. We also keep the area around and on top of the tower covered with leaves or straw overwinter to minimize freezing depth.
Harvesting the Castings
Harvesting the castings from our worm tower is simple. Come spring, all the worms migrate upwards to the top third of the tower in search of fresh kitchen scraps, so we set aside the wormy top third to replace after harvesting. Then we use a trowel around the inside edge to loosen up the castings and any small roots that have entered the holes from the surrounding perennial plants. Then remove these pure castings by hand and place them into a bucket for Becky. She now has these amazing castings to integrate into her potting mixes or compost.
What we like about the worm tower is how easy it is to make and use. This is a simple and clean way to dispose of kitchen scraps while feeding our gardens at the same time.
And by the way, is there any reason that drilling a bunch of holes in an old 5-gallon bucket and sinking that into the ground would not work as well? One would just want to be sure it is mulched heavily over winter to prevent the worms from freezing. And the lid is bigger (a bit more unsightly?) but one could cover that with a potting base and put a nice potted plant on top of that for looks! What other variations might there be on this theme? And what other materials might we use besides plastics?
What About the Potential Toxicity of PVC and Other Plastics?
87 thoughts on “How To Build a Worm Tower”
I first spotted your worm tower idea years back and jumped on it. My garden in Racine county, WI , featured 2 of them for years. (A third was poorly placed and failed. Heavy clay soil resulted in a flooded worm tower when it rained). The big difference is I salvaged PVC culvert pipe to make mine. So they’re nice and wide. Easy digging! I use a post hole digger to harvest castings. They finally died out (not sure the cause) and I need to replenish my worms this year. But winters were just fine for many years. I stuffed the towers with fall leaves and that always got them thru til spring.
Thanks for sharing your experiences!
I built a worm bin and insulated it so it would stay warmer all winter. My only probem with the red wrigglers were they got addicted to fruit scraps, apples, melons, pears, and other fruity wastes. They would only munch on the sweet stuff and ignored the other vegetables, cabbage, carrots, onions etc. I got huge amounts of castings but ran out of space to use it. I wonder if I could semi dry it out and bag it for later use of give-a-way bags. Maybe the kind of bags that animal feed comes in. Breathable but contained. Any comments welcome. B.T.W. my curbside garbage went down considerably and kept it from landfills.
Great idea to insulate! I’ve buried a worm bin and covered it with straw to overwinter, now I just take a much smaller population indoors to my basement for the winter.
I think the vegetable waste needs to break down longer, they actually eat the things that eat the scraps. I bet it will all be eaten eventually.
You’d have to keep feed bags dry so they don’t leach out but if you have them as a resource, I bet you can make them work.
Please set me straight on how the towers work. I thought the purpose of the holes was so the worms would go in and out of the pipes (even though I found it amazing that they might have memories to find their way in and out!). If the worms DON’T crawl out, then why do you need holes? If they DO crawl out wouldn’t they leave their castings as they go? On the other hand, if I were a worm and found a food heaven, I don’t think I would leave. So then you have to dig through maggots etc, to get to the good stuff? Yuck. Please tell me it’s not that unpleasant.
There are no maggots. The worms they’re talking about are red wigglers.
The holes in the tubes allow the compost tea(juice from work castings) to drain into the soil around the tube feeding the plants around it.
And in the spring you are left with rich compost, no maggots.
Maggots are fly larvae, and if you keep the food scraps in your tube covered, flies don’t go anywhere near it
Update on 60 gallon tower.
Last fall before winter I shovelled it out and there was very little breakdown of the contents and I saw only 1 worm in the whole bin. I was kinda dissapointed actually.
But after having the garden rototilled the awful stink was gone and by spring you could not recognize any of the contents. It was also amazing fertilizer.
I’m sure there was more worms than the one that I seen but I do still consider the project a success. My goal was to keep as much garbage as possible out of the landfill and this was the best way to address the food waste issue.
I was hoping it would never have to be emptied but 1x per year isn’t bad.
One thing that I did notice was a huge amount of maggots in the bin. They are gross but if they help break down the waste even a little bit I don’t care if they are in there.
Most worms will not benefit from oils, dairy, or citrus products being mixed in with the kitchen scraps. Might need to separate those things out and mix them with soil so that bacteria can work on them separately first, then add them to the regular cycle once they are partially decomposed.
If the pile is big enough worms can self regulate, no need to seperate.
Onions can be trouble too.
How far apart do you put the worm towers to get the maximum benefits. Also, I heard that earthworms are better for your garden and composting worms are for composting. So, should I get earthworms for the towers. Thank you
The red wigglers love the slimy stuff and tend to stay near the litter on top. Earthworms travel through the soil profiles thus opening up water and air pathways deeper down. They are both valuable. So, the wigglers will love the constant supply of kitchen scraps going into the tower. Put the towers wherever you have perennial systems, bushes or trees that can will have long-term rooting systems. Your annual veggies 5-6 feet away will not benefit much from a worm tower.
Hello, why do you recommend the tower only for perennial systems, bushes or trees that have long-term rooting systems? i would think a worm tower would be a great option for an annual no-till bed for any plant, yes?
Last summer mine had lots of maggots in it which seemed to reduce the smell and help reduce the volume a little bit. I throw ALL kitchen waste in mine and shovel it out in the fall. It depends on your goals with the tower. I am just happy to get rid of kitchen waste. If it helps my garden a little bit with a form of compost I’m happy with that. I did it with the main purpose of keeping food waste out of the garbage can. The maggots are gross when u open the lid but thats only for a minute when you throw a pail full of waste in.
Maggots are great fishing bait. I have caught many a fish of many types with maggots.
I love this idea because my husband hasn’t been a big fan of the worms under the kitchen sink! I was wondering if anyone has had trouble with larvae taking over the tower. I had been adding waste, and when I went to check after being out of town for a couple of weeks, the entire tower was filled with some kind of larvae. Any ideas are appreciated!
Are the larvae white/gray, segmented? It might be black soldier fly. Harmless, keeps the fruit flies out. Feed for reptiles and other.
Yes! That’s exactly what they look like. I’m glad to hear that. It’ll keep the little garden lizards happy. Thanks!
If it’s black soldiers, you can throw any leftover from your kitchen without any doubt. Diary, citrus, meat, even cooked foods won’t be a problem. When I first saw them I ve been scared so i made some search about them. The only problem (if you can say that) is that they have higher metabolism rate than red sprinklers and they will leave less compost in your tower. But!!! The more you give them the more they compost it doesn’t take more than 2 days to turn everything black. In my garden they come in April and I understand that they are there because my bin is going down rapidly. They compost in really high speed and I ve read they make life easier for red sprinklers (they can happily share the same place) which are composting after them and make compost even better. I wish they could stay longer in my garden but they disappear with first frost.
Let them stay. They help break down the waste and control the stink.
Your larvae (maggots) could be Black Soldier Fly larvae. They are actually more vigorous at consuming a larger variety of kitchen scraps than the red wiggler worms, particularly attracted by stale bread, pizza crusts, etc. The adult looks a lot like a black wasp, but is harmless and doesn’t seem to be capable of flying very far or fast. I have had some issues with the larvae turning into a garage full of adults when I bring my portable worm bin inside for the winter. I like the idea of the worm tower as an alternative for this reason. Black soldier fly larvae are flatter and longer in body size than house fly maggots, quickly inch away when uncovered, and leave behind a consumable dried ‘sleeve’ when they pupate, and will go dormant when food supplies dwindle. All of these attributes make them wonderfully better than normal maggots.
My bin was full. I shovelled it out into the garden and noticed very little decomposition and saw only 1 worm in the entire 60 gallon barrel.
I’m going to try it again and if it dosent work I will just consider my bin a “holding area” to throw waste until it is full. Then I can just dig a hole in the garden 1 or 2 times a year and let it trench compost.
would love to do this, but in the 30 years I’ve lived in Phoenix, I’ve never once seen a worm.
The worms definitely need to stay moist. The desert may not be the best place for this type of thing. You could do it if you could create the right environment but it may take more effort than it’s worth. Perhaps a worm bin would be more appropriate?
Yes! That is probably why I won’t do this, as keeping it consistantly moist all year will be more trouble than I think it would be worth. Plus, if I understand correctly, Phoenix temps are right on the edge for the red wrigglers, and I don’t want to be responsible for mass murder during record temps!
But, in case I change my mind: 1) Will this work okay in a flood irrigationsystem?
2) Also, I have seen set ups where someone puts these in raised garden beds. Why do you not recommend this?
I think you’d be testing if it worked with that type of irrigation system!
In my mind raised beds aren’t functionally different from the many other types of beds. If I thought it was appropriate I’d try it in any of them.
Good luck!
I’ve lived in Phoenix for 45+ years. Of course there are worms! But, it will depend where and when you are digging. Are you digging in hot, dry, soil? Super sandy and rocky? or lots of clay? Or is it slightly shady with lots of hummus? Do you use chemical fertilizers and/or insecides? Has it rained recently? Do you have flood irrigation? Sprinklers? Drip tubes? Or are you just setting up with one of these? Are you just digging in the top 2-3 inches or deeper? All these things, plus the time of year will affect whether or not you see (native) worms.
Start with worm bins or totes. Make raised beds with only organic additives. Create an environment for them then start your worm tower in your raised beds. Hope this helps
I will continue to throw in kitchen scraps all year long. Just hoping the worms will chomp them down as fast as I throw them in.
But will the level drop when it thaws and after that happens will the worms keep up to deposits?
Once it thaws the level will drop. You’ll need to keep feeding them throughout the growing season. If you don’t continue to feed them they will eventually stop making deposits.
I’m new to composting of any kind and just hoping that my oversized 60 gallon worm tower will work as planned. As said right now it is almost full and is a frozen lump. When it thaws will the level drop quite a bit?
If it’s embedded in the ground, especially if its down below the frost line, it should be OK.
Nice thing about this is that by the time we get our yard done the worm population should be established and the soil will be nice for planting.
I built my extra large worm tower with a 60 gallon barrel. I drilled 3/8″ holes in the bottom and the sides about 1/3 up the sides. I buried it so that only 10″ are sticking out of the ground. I got a cement ring to go around the top part and on top of that is stacked 2 rows of fire pit bricks so it looks like a fire pit in the corner of the yard. I have a steel lid that keeps it shut tight and makes it easy to add scraps to it. I built it pretty late in the year so I didn’t add worms before winter. I have been adding kitchen scraps and also the cardboard tubes from toilet paper. The bin should be big enough to handle a winters worth of waste and in the summer I can add worms if necessary.
Sounds great! I’ve had success (admittedly in some mild winters) by digging a pit, putting my bin there and covering it with straw bales. I’m also managing a farm where they installed a 4′ x 6′ worm bin that goes down 4′ into the ground. We’ll see this spring how well it’s worked!
With the bin that goes down 4′ how well does it work?
With the 4×6 pit how long does it take for a pail of waste to be eaten by the worms? How often do you have to empty it?
It sounds similar to my 60gallon tower which has been working great the last couple years. It is close to full by the end of winter but the level drops and there is enough room for a summers worth of kitchen scraps.
In the fall I shovel it out before the fall tilling and start over again.
Sorry, forgot to check the “email when new comments are added” box.
I have raised beds, four 3×6 and four 3×9. Would one tower per bed suffice, even for the larger beds?
This is also my exact set up. Hoping to hear a response!
You could easily put two in the 3×6 and 3 in the 3×9.
Thats my plan…2 per bed. I dont go that deep though. Just a foot.
Will worms just show up or do they have to be added?
You have to add worms, they are a special kind. Worms from the ground won’t work the same way. Red wigglers are what you need…
Why do you think native worms won’t work? I’d rather let nature take its course, in case there are times I can’t be keeping the tower ‘fed’. In this case, I’d like native worms to come back when I’d start back up. And it would be 1 less thing to manage. I’m ok with the process being slower.
I’m inclined to go the “native” worm route as well. I already mulch garden and have so many worms that I could probably sell them as bait if I didn’t cherish them as my little helpers. They make short work of my spoiled hay so I suspect they would quickly find a bucket banquet. Also I have heard that red wrigglers don’t like real cold weather (not sure about heat).
BTW, what is the reason for having the top be so high? Ease of access as plants grow? Not get lost in garden? Winter snow?
Also, would it be OK to just use a lidded bucket? The screening might add ventilation, I guess, but is ventilation necessary?
To my knowledge there are not any native worm species in North America. The worms for these systems are Eisenia fetida, red wiggler worms. They live in a plant litter layer and are better for compost as opposed to the worms you might find in your soil.
The top was high because that was the container we had that fit the tube. If you’ve got something else try it and see how it works. The bucket might work but the worms do better with more ventilation. They start to crawl out if the situation is not to their liking, keep an eye out for that to see if the lid is not working.
I found this article about native earthworms – just the basics.
http://www.straightdope.com/columns/read/1916/whats-the-story-on-north-american-earthworms
I just bought enough pip for 6 more worm tubes. I make mine tall so you can get to them in season when plants are tall. I do this in my veg garden.
Would the material break down/be eaten by the worms fast enough that 45 gallons would be big enough? My goal is to reduce waste that I have to place on the curb so I want to let the worms do as much as possible. I’m not really interested in harvesting any compost, just getting rid of the organic material which will reduce my total garbage significantly. Thanks for the first answer!
Would it work to build a much larger version of it with a 45 gallon drum so that all kitchen waste, grass clippings, garden waste, and even paper could go in it?
How long of a piece of pipe should I use to handle kitchen waste for a 2 person household?
Hi Jan…
The pipe we used is 28-30 inches long. So far our worms have made it through every winter so I am assuming that they go to the very bottom. Be sure your tube in deep enough for that. Then regarding how much they will hold it totally depends upon how many kitchen scraps you generate, so you may get by with one or maybe you will need three of them. Ours is always full and as the worms eat it down, we add more to it. If we have extra material (which we do with a family of 4) we have other compost bins we use it in.
Hope this helps….Bill Wilson
I love this idea. But I wonder if anyone has thoughts about materials other than PVC. I would prefer not to buy any PVC unless absolutely necessary. And wouldn’t it leach?
How about a 5-gallon bucket?
If PVC gets hot (and it will when composting stuff, especially in the summer) it can release Chloride, So please look for HDPE (or other food graded plastic.) You can buy HDPE pipes at construction stores. They are used for drinkingwater systems (where PVC is banned, at least over here in Holland). For this reason we use only HDPE tubes and barrels for our gardentowers / groenteraketten.
Otherwise: great idea, the simpler the better I say!
My concern would be that a long time use of PVC might result in a release of some of the toxic compounds used in its manufacture as the pipe warms up. Specifically DBTI and TBTI (dibutyl tin oxide and tri-butyl tin oxide) both biocides and carcinogens used as catalysts to make PVC. Additionally PVC gets very brittle when cold and can shatter if it freezes with water in it. Found that out when using it for rainwater collection totes. High density polyethylene containers are a better choice although they to will break down in UV light in time.
I am an avid indoor vermicomposter and use red wigglers (Eisenia fetida) in my multiple bins. I have been considering creating an outdoor set up but I have also red that the wigglers are non native invasives. From most of the research I have done it seems they only have a damaging effect on hardwood forests. Do you have any evidence that they would make a damaging effect in a garden?
I’ve got one in my garden here in the desert southwest of southern Arizona. I just need to find some worms to put in it. I
Vermilion Womery has them for sale in Oracle. Pet Smart sells Red Worms about 150 count for 4.00. 5 years ago we started out with two containers and now have over 10,000 worms in our worm bins.
I kept a worm box made out of wood sunk into the ground 2 feet made it to fit a bale of straw and threw food scraps by lifting a section of straw. It held the moisture pretty good, but I like this tower idea because the cold in Wisconsin gets bad enough to sink lower than two feet. This winter was brutal. I think I’ll try a small drum if I can locate one. Thanks for this info. I hope to visit some time this summer.
Grew up in Madison, WI; now live @ stateline WI/IL. As a child, frost line depths in Madison area were 31″-36″ (that was back when typical Feb temps were -20F for three weeks at a time, and when the 24″-30″ snows were common). The deal with frostline is SNOW or the lack of it. When snow remains on the ground, frost lines are less deep; and when snow is largely absent during the coldest parts of winter, the frost line can deepen to 40″ and more. There is the matter of whether your site is on the sunny side of your house during winter or the N side that may be more shaded.
Those worms won’t travel that far so I would place the towers about 5′ or 6′ apart.
If I wanted to make more than one tower-how far apart would you recommend I place them?
How will this composting idea work in Texas? Do you have any data on its use in the N. Tx area? I love the idea but sometimes what works in other areas does not translate to our heat prone areas. I would like feedback from any gardeners in my area who have had success with this method. Thank you, MH
We don’t have any information about how this might work in TX. I would be most worried about them drying out but being in the ground provides a great deal of protection from heat or cold. Why not try one out and let us know?
I’m planning to build one out of a plastic 55-gallon drum.
Let us know how it works! Since it’s a bigger volume I wonder if you’d have to harvest the castings…
I built one before winter with a 60 gallon plastic barrel. I have been adding kitchen waste to it all winter and it isn’t full yet.
I’m hoping that in the spring time it he level drops substantially and at that time I can add worms if necessary.
How has yours been? Have you had to empty it? Have you added worms?
Right now I am just hoping it works good because if not I will have a 60 gallon barrel that will really stink if nothing happens with it!
How did it work out for you?
I am new to composting with wigglers.. So far so good with my Rubbermaid buckets.
My question is in the towers, the worms move out of the tower thru the holes and then back in to feed?
So I could put these in my garden and then wouldn’t need to deal with the buckets on the back porch? That would be nice!
I love the idea, but would be wary using PVC. Any suggestions for healthier alternatives?
What state is the picture from with the nice green lawn? I live in dry arid Colorado. I am jealous.
Just wondering if this would in Canada where the winters are 5-6 months long and temps. can be as cold as -20F and colder?
Thanks
Some variation on this might work. I would make sure that it is at least down to the frost line and/or very well insulated. With the insulation you could also add compost that heats up (which you usually don’t want to add). Perhaps have it be a double tube with straw on the outside and the compost in the middle? You’d still need holes so that the worms can get into the soil.
I bought an above ground worm tower … pricey, but worth it. I have been extracting loads of vermicompost to use in my garden. It’s been wonderful.
After reading this post though I can see the incredible value, especially during the cold months when digging through frozen dirt would be an issue or while your plants are growing … what a wonderful idea!
Definitely sharing this.
Great idea. Raised red worms in my basement for ten years and ate all my ” waste” from the kitchen during that time. Got to be to much trouble and then had to remodel basement for more room so gave the farms to my neighbor and they have kept them going for the last three years. My question is how do you remove the castings from your sunken pipe once a year as recommended in the article?
I think I will try this and get some worms back from my neighbor to get it going.
It’s pretty easy to just reach your arm in and pull the castings out. I’ve myself had a project where I’ve buried my rubbermaid worm bin in the ground for the winter, and then pull it out in the spring. It operates like a normal worm bin when it’s warmer and goes dormant when it’s cold.
I’m wondering if a post hole digger would work?
Lisa, that’s exactly what we used.
Lisa… we used the post hole digger to make the hole for the worm tower. I use a hand trowel to remove the castings. See my notes below.
A 2016 update…!
I’m working on our website and found this thread. Since I’m the one who empty’s the wormtower I’ll share how I do it.
During the winter, the area over and around the wormtower is covered with a straw mulch to keep the frost from going too deep in the winter. In the spring I start to add new scraps to the top and worms migrate toward the food and warmth. I then reach in by hand and remove the top 40% of the content and put it into a bucket beside me. This is all of the slimy stuff (no smell) and the worms. Below that is pure worm casting with a variety of roots tangled within it from the neighboring trees and shrubs. I use a hand trowel to loosen everything from the sides and cut the roots, using my hands to scoop out the worm castings.
Then I throw a bit of green and dried grass into the bottom before returning the worms and slime to the tower, topped off with fresh kitchen scraps and the process begins anew for the next year. Good Luck…!
Thanks for updating this! Ive had a indoor worm bin for a couple of years and thinking of doing towers in my garden. I was wondering how the plants looked next to the tower(s)? Ive heard that the leachate isn’t good to put directly onto plants, and Im guessing that would seep into the dirt as time goes on. But the castings are great but seems that you still have to separate them out each year. So wondering if its having a passive healthy effect on the plants or its just easier to keep outside?????
Great article! One spelling error…( food waste and in tern, fertilize the garden bed. )tern should be turn.
Thank you for sharing!
Thanks Roxane, glad you enjoy it. It’s all fixed!
Here is the Slow Down Farm Worm Tower I installed in my raised bed. Dale, There is a link to your site and instructions too!
-Ryan
I love worm towers! we are constructing a large kitchen garden in front of our house and we will SURELY incorporate several worm towers. THANK YOU for these easy-to-follow instructions!