This is a topic that is definitely long overdue for discussion here on the blog. In a sad twist of irony (since I’ve been planning to write this post for awhile), I actually received an email from one of my customers last night reporting that he had lost all the worms in one of this bins due to overheating.
I guess part of the reason I don’t think about this issue too much myself is because I generally don’t use large plastic tubs for indoor vermicomposting. As I’ve written recently, my big wooden outdoor bin has been overheating this summer, but it’s generally not a major concern because the worms can simply move to the outer edges where temperatures are considerably lower (moisture is able to easily evaporate through the spaces between the boards).
Heating in a worm bin is essentially the same thing that is occurring in a large compost heap. When it comes down to it, any time you combine nitrogen-rich materials (eg food waste, manure etc) with carbon-rich materials (eg. shredded cardboard, fall leaves, straw) and provide your mix with moisture and oxygen, it is going to heat up. If you have enough mass – generally anything over 1 cubic yard – you will stimulate full ‘hot composting’ conditions – but even with much smaller volumes of material enough heat can be generated to cause harm to worms.
Generally, it is when you are first setting up a system that this is most likely to be a major issue, since you are adding a bunch of materials at once. Also, as mentioned, the likelihood of this being a major issue increases as the size of your system increases. Once your system is up and running and has reached an equilibrium (or close to it anyway), you won’t likely run into too many more heating issues. You can still definitely get hot zones in larger systems – especially those influenced by hot outdoor temperatures, but it’s still less of a concern.
So how do we prevent disaster from striking?
Aside from simply becoming aware of the potential for overheating when setting up a larger system, I highly recommend that everyone adds a compost thermometer to their vermicomposting toolkit! Aside from the worms, it is definitely a vermicomposter’s best friend!
If you can’t find one locally (and don’t want to order one online), feel free to use a meat thermometer instead (or even a health-related thermometer) – the longer the probe the better, however. You definitely want to be able to reach all regions of your composting mass.
I also (as always) recommend that systems be set up well in advance of the addition of worms – obviously this won’t always prevent issues (as illustrated by my customer’s disaster), but if you also use a compost thermometer, and only add worms once the system has cooled down, you’ll certainly be better off.
Of course, systems can also overheat after the worms have been added – in fact, the worms themselves can even act as a catalyst of sorts. Whether it be the result of moving materials around or the addition of castings to the mix, they can actually help to stimulate excess microbial heating, thus ending up at least partially responsible for their own demise. As such, it is really important to keep an eye on temperatures in the bin for the first while after adding your worms. If you see the temperature starting to rise past 30 C (86 F), I’d highly recommend splitting the contents of the bin between several different containers – preferably without lids to allow for more air flow (and thus cooling).
This is yet another limitation of using plastic tub worm bins – because they don’t allow for much air and moisture release, heat is slow to dissipate once generated. Wooden bins are great for keeping worms cool, especially if they have spaces between the boards. Unlike plastic, wood can actually ‘breath’ – that is, allow moisture to pass through, thus helping to keep the contents cooler.
Anyway – just some food for thought, especially for those of you planning to set up larger systems!
By the way – if you live in a colder region, you can actually use this excess heat to keep your worms warm in the winter, but you’ll definitely need some insulation and quite a lot of organic waste to ‘fuel the fire’ so to speak! You’ll be hearing a lot more about cold weather vermicomposting later this year, so I’ll leave it at that for now.
[tags]composting, hot composting, vermicomposting, worm composting, worm bin, compost thermometer, thermophilic[/tags]** It's a Great Time to Get Serious About Worm Composting - Save $30 on the CG "Ultimate" Package - Click >>Here<< to Learn More. **
This question comes from Cindy – she is wondering what she should do with what seems to be an overcrowded worm bin.
Hi, I’m new to worm farming, and I really find it
interesting. I have a plastic bucket farm with wire screen over
bottom holes, and a screen mesh top. I hae a piece of burlap over the
I got my worms May 21st, and at the end of June, I gave them a fresh
bin, and moved the black gold to the garden.
Now my worms are getting bigger and more plentiful. I came home this
week to find 20-30 worms trying to crawl out of the container. I’m
wondering if they have reached the end of their current
bedding/compost and are looking for more food?
I’m also wondering if I should glean out a bunch of worms with the
bedding change and add them to my garden? Will I need to feed them in
the garden? The current worm farm is in my cool basement, will the
summer heat be too much a change?
Will the liquid from my current farm, help get the new bedding ready
for worms faster?
Also, I’m wondering what happens this winter when I have too many
worms, and the garden is frozen outside…my turtle can only eat so
I guess I’m looking for ongoing maintenance info.
It sounds like you are doing quite well for someone who is “new to worm farming” – congrats! The fact that you have already been able to harvest vermicompost, and your worms are breeding quickly is definitely a good sign.
If the worms are trying to climb out, it may indeed be an indication that you need to refresh your bedding materials yet again, or better yet, split your worm population and start up a second system. How does the material in the bucket look to you? Is it dark and crumbly, or is there still a significant amount of unprocessed materials? If it is mostly made up of processed bedding/food (ie vermicompost), then you are likely right. If on the other hand there is still a lot of unprocessed bedding/food there may be something else causing the worms to want to leave.
I generally wouldn’t recommend adding composting worms directly to your garden since they are not really soil worms, and will more than likely leave the area or die if they are unable to find a decent amount of decomposing organic matter. As I’ve discovered this year, vermicomposting trenches can be a great way to keep your red worms active in the garden – it’s like setting up an inground ‘worm bin’. The major difference is that the plants can make direct use of the vermicompost as they grow. You may also want to try out what I’ve referred to as ‘Garbage Gardening‘ – basically you lay organic waste directly over the soil, then add some sort of mulch over top – once it has aged a little, it should make for an ideal habitat for your composting worms, not to mention an excellent bed for growing plants.
If you live in area that has a real winter, I can’t imagine that it would be too hot outside in the summer for your worms. We have some pretty hot weather hear during the summer months, but I’ve had no problems with my worm gardens. Unfortunately, I can’t say the same for my big outdoor worm bin – it has been overheating periodically. Just make sure you have a thick layer of mulch (straw is ideal), and add some water periodically if you are having a dry summer.
It will be tough to keep your outdoor systems completely active during the winter months – unless you have a pretty major supply of organic waste, but it should not be difficult to at least keep most of your worms alive – especially in the trench systems (since the earth will help to protect them). The key is to add a LOT of bedding over top – fall leaves, straw – whatever you can get your hands on. It wouldn’t hurt if you added a lot of food waste as well.
As for what to do with excess worms during the winter – here are some options:
1) Give them away or sell them (just post an ad on any free classified site, like Craigslist etc, and you’ll likely get some takers) – you could also encourage friends and family members to get into vermicomposting.
2) Start up another vermicomposting system – I’m sure you could find room for a few small worm bins in your basement.
3) Have you ever tried fried worms? Mmmmmm…
Ok, I’m KIDDING!
Oh – almost forgot – the liquid for your bin is probably ok for soaking your new bedding IF you let the bedding then sit for a few days before adding worms. Straight from the bin it will likely be pretty anaerobic and potentially harmful to your worms. Cardboard soaked in it then allowed to sit would likely be fine after a few days since aerobic microbes would likely breakdown any anaerobic bi-products that may have been in the liquid. If it REALLY stinks though, I would avoid using it altogether.
Anyway – hope this helps, Cindy!
[tags]red worms, red wigglers, garden, gardening, worms, worm composting, vermicomposting, worm bin, vermicomposter, composting, winter composting[/tags]
My vermicomposting trench has helped me grow big, healthy plants this season.
I think I provided a decent overview of my vermicomposting trench system with my first post, but I thought it might not be a bad idea to add a follow-up – this way I can fill in some of the gaps and provide a general update on my progress.
As you can probably tell from the image above, my plants are continuing to thrive thanks to their close proximity to the trench (no I don’t have scientific proof to back it up – but let’s just call it a ‘hunch’ on my part! haha). As you may recall, I’ve added no inorganic fertilizers this year, yet my tomato plants are quite a bit bigger than the maximum size reached by my (fertilized) plants last year. I’m looking forward to seeing how my crop turns out – I’ve done absolutely nothing with the plants other than support them (after they started falling over), so I’m not sure that the quality of the tomatoes will be as good as it could have been, but we shall see. There are loads of really nice looking green tomatoes now, so I’m sure there will be at least a few good ones harvested.
My zucchinis have certainly been growing like crazy as of late. We’ve been enjoying some of them on the BBQ already – delicious! I can’t get over how quickly the plants are replacing the ones being harvested, and just how quickly the individual zucchinis reach a good harvesting size! I think just for fun I may let one of them continue to grow, just to see how big it will get!
There were some great questions asked after I wrote my last trench post, and while I did do my best to answer them in the comments section of that post, I thought it would be beneficial to include some of those topics in this post as well. Here then are some of the things people have been curious about:
Heat / Cold – One of the great things about an in-ground vermicomposting system is that it is protected from weather extremes. In comparison to an above-ground worm bin for example, it will generally be easier to keep temperatures cool enough during the hot summer months, and be able to prevent it from freezing during winter months.
I’ve definitely been having a lot more trouble with overheating in my large outdoor worm bin than in my trenches. That being said, when you first set up the trench (and add a considerable amount of organic waste at once), you will need to be more careful – at least if you are planning to add composting worms. You are probably better off waiting for a week or more, and even then you should take temperature readings to make sure it’s not too hot. If you are adding mostly ‘brown’ (carbon-rich materials), or are building the trench in the early spring or fall (when cool), this likely won’t be as much of an issue.
Someone asked about issues associated with being in direct sunlight (fairly important for the success of a vegetable garden). While I suspect that my approach just isn’t feasible in some locations where it is very hot and dry, I’ve personally found that keeping a nice thick layer of straw (and other ‘brown’ organic matter) really seems to help keep the moisture in and the heat out.
I can’t say for sure how well the system will respond to really cold weather. I suspect my larger sandbox trench will stay quite warm during winter months (assuming I add lots of food waste and bedding materials) – not so sure that the other trenches are large enough to hold significant heat. Either way, I’m sure a lot of the worms will still survive the winter (I’ll definitely add lots of straw and leaves over top before the snow starts flying.
Adding Materials to Trench – Depending on the quantity of wastes you have access to on an ongoing basis, you’ll likely want to go with either a ‘continuous’ or ‘batch’ approach. I suspect that for most regular homeowners the latter approach will make the most sense, since they won’t have a constant supply of organic wastes that need to be dealt with. In this case you would simply stockpile your materials, build your trench (likely in the fall or spring), then simply let it sit and compost without further additions. Or perhaps you would simply add more materials (lawn clippings, weeds etc) as they became available.
In my case, it’s been important for my trenches to be ‘continuous’ systems due to the large amount of food waste I’m receiving daily from the restaurant. When treating your trench as a continuous system, it becomes even more important to optimize your methods. As I’ve discovered, it is quite important to chop up materials fairly well before adding them to the trench. Out of curiosity I tried adding whole broccoli stalks (one of my most abundant waste materials) to my main trench. It was amazing how much more slowly they decomposed in comparison with those chopped up with a spade beforehand.
All I’ve been doing when adding new materials is simply pulling back the thick layer of straw (and grass clippings), adding a layer of waste 2-4 inches thick, then covering back up. On occasion I’ve been adding some egg carton cardboard underneath the food waste to help provide more structure for the worms and help to balance the C:N somewhat. Eventually, as the overall level of materials in the trench sinks, each top layer of straw becomes the base upon which new food waste is added, with a new thick layer of straw added over top. Straw is an excellent material to use if you are planning to have worms in your system – Red Wigglers just seem to love crawling around in and munching on moist rotting straw. When there is rotting food waste in there as well, it becomes an excellent combination of habitat and food source – not unlike a well-aged manure and straw mix.
Moisture in the Trench – As with any composting system, moisture is certainly an important consideration. This is especially true if you live in an area with really heavy clay soils and/or abundant rainfall. Too much moisture in the trench can create anaerobic conditions and slow down the decomposition process – something that it probably unavoidable near the bottom of your trench due to the lack of air flow. Situating your trench directly beside water loving crops like tomatoes and various members of the cucumber family should certainly help, especially during dry summer months. The composting worms themselves should also help to aerate the system somewhat via their movement within the decomposing organic matter.
As I discovered, things can really slow down during periods of consistently wet weather – I’m sure this wouldn’t have been so noticeable if my worm population in the trench at the time had been higher. I will definitely be interested to see how the system performs once the wet fall weather arrives. I should have a lot more worms by then, but I won’t have the jungle of plants and hot weather I have now so it might be a bit more challenging – I suspect the trench will become more of a windrow since the level of materials will likely continue to rise above the ground.
Anyway, looks like this follow-up post is getting a little longer than I had planned to make it – but of course, I still don’t feel like I’ve covered the topic completely. Oh well – I’m sure I’ll provide more information in the video I’m going to put together, and will almost certainly provide a few more updates over the next couple months.
Yesterday I wrote about Robyn’s creepy-pants-inspired vermicomposting system – the ‘Worm Inn‘. Well, it seems Robyn isn’t wasting ANY time moving forward with this (whoohoo!) and I already have an update for everyone.
If you are interested in browsing Robyn’s selection of Worm Inn designs and potentially buying one, be sure to check out her shop over at Etsy.com: Nomad Needles. I didn’t realize just how large the system is until I saw one of the images with a person (Robyn’s friend, in case you are wondering) standing next to it. Now I’m even more impressed! It’s clearly more that just a fun little system for trying out vermicomposting – it looks to be comparable in volume to a medium-sized indoor worm bin.
Given the fact that Robyn is making these units individually by hand (well ok – using a power sewing machine – haha), and given how great they look (not just your average worm tub), $55 for one of these is an awesome price. There are plenty of small flow-through worm systems out there these days costing upwards of $100 (or more)!
In my opinion, a system like this would make a fantastic gift for someone thinking about getting into vermicomposting. Most worm bins are pretty ugly and/or boring, but that certainly won’t be an issue with the Worm Inn. I’ve never seen such a wide colour/pattern selection available for anything relating to worms!
Robyn has informed me that she’ll be putting together an ‘official’ Worm Inn website before too long, so I will keep everyone posted on that. In the meantime, be sure to check out her Etsy store and help a budding ecopreneur out by buying one of these systems!!
[tags]worm inn, worm bin, worm bins, vermicomposting, worm composting[/tags]
A couple weeks ago I wrote a post about brewing your own microbial soup as a food source for your worms. As mentioned, it is relatively easy to breed your own population of assorted microorganisms simply by adding organic matter to a bucket of water then providing some aeration.
Shortly after writing that post I actually learned the hard way that using smelly (anaerobic) liquid is generally NOT a good idea, as it can contain bi-products (like alcohol) that are harmful or even fatal for your worms. Luckily my mistake didn’t cost me too dearly (only a few dead worms), but it was definitely a valuable learning experience.
Anyway, I’ve decided to make some more microbe water – properly this time – so I can test it out and see what the worms think of it. I’ve added a handful of grass clippings to a bucket of rain water, along with an air stone (connected via tubing to an aquarium air pump). Within a few days I should have myself a yummy concoction.
As mentioned in my previous (microbe water) post, I want to soak cardboard with this liquid and add it to one of my worm bins, along with some cardboard that has been soaking in plain water. It will be interesting to see if there is a major difference in worm colonization rates.
Should be fun!
[tags]microbes, microorganisms, microbial, protozoans, worm food, worm bin, worm composting, vermicomposting[/tags]
There is nothing quite like having someone take one of my goofy ideas and really run with it! One of our faithful readers (and worm friends), Robyn, did just that. She was inspired by my ‘creepy pants vermicomposter‘, and decided to create her own version – a flow through system she is calling “The Worm Inn”.
Robyn is very humble about her creation – she was even a little shy about letting me post pictures on the site! Thankfully I was able to convince her that the Worm Inn needed to be seen – after all, it is probably the coolest homemade vermicomposting system I have seen in a long time!
Like the Creepy Pants vermicomposter, the Worm Inn is a hanging, flow-through vermicomposting system. Food and bedding materials are added from the top, and (eventually) worm compost can be harvested from the bottom.
Unlike the Creepy Pants, Robyn’s creation is compact in size (much more convenient for smaller spaces), and includes some really nifty features. For starters, she installed a handy drawstring tightening system at the bottom – so no need to mess around with annoying cable ties.
Robyn also included a fine mesh cover at the top to discourage flying pests from easily getting in and out – a great feature for a system like this, which is definitely more prone to invasion by fungus gnats and fruit flies.
The unit even includes a handy little pocket on the side for holding a water-bottle – something that is really useful to have on-hand at all times (since the bedding can dry out very quickly). This may seem to be of minor importance – but for someone like me who always seems to be misplacing things (like water bottles), it would prove to be quite beneficial I’m sure.
The Worm Inn can be suspended virtually anywhere using bungee cords (as shown in the first image), but it also works quite well with a standard laundry hamper stand (see image below) if you prefer keeping it in a location closer to the ground.
Being the eco-entrepreneurial guy that I am, I quickly saw more than just a nifty worm bin in Robyn’s creation – I saw the potential for a really cool product she could make and sell online. It seems that Robyn was already playing with idea herself, but she appreciated my encouragement (aka enthusiastic raving – haha) nonetheless.
Should be some interesting Worm Inn updates on the way!
[UPDATE – 08/05/2008 – check out Robyn’s Etsy store to peruse her selection of Worm Inn designs]
[tags]worm inn, worm bin, flow-through, worm swag, creepy pants, vermicomposting, worm composting[/tags]
Here are some questions from Tomas:
Hi! I just have a few questions about worm composting.
1) When maintaining worm the bin, do I need to manually stir the
bedding and mix it with the food ?
2) I heard from someone that red wigglers don’t do well in its own
compost and will die if the compost is not taken from the worm bin as
soon as possible. Is this true?
3) Do I need to make holes on the lid of my bin for air ?
4) The new bin I made is layered with alternating layers of food and
newspaper. Does it need to be layered?
5) Does the food need to be place at the top of the bin or can food
be placed anywhere?
6) Do I need to mix soil in the worm bin with the other organic
materials I put in the bin or is the organize material on its own ok?
1) Some recommend stirring the bedding periodically to help aerate the bin and ensure that moisture is evenly distributed throughout. I personally prefer not to do too much of this once the worms are in the system since disturbing their habitat can cause them stress. It’s a toss up though, since increased aeration can prevent anaerobic conditions from developing and help to accelerate the production of vermicompost. When adding food, I recommend simply pulling back the bedding and dropping some food in, before covering back up. If it is a sloppy wet food material you may want to add some dry bedding in the hole before adding it, to help absorb excess moisture.
2) That’s not really true. While Red Worms certainly won’t get much nutrition out of the well-processed material (which contains a lot of their waste products), it doesn’t quickly reach toxic levels or anything like that. Back in early July I wrote a post about harvesting some vermicompost from my big outdoor worm bin. As mentioned, I found countless tiny Red Worms in the finished vermicompost, so while they were clearly suffering from a lack of nutrition, the material couldn’t have been seriously toxic (if at all) even though it almost certainly contained a very high percentage of worm castings by then (since I’ve never harvested material from that bin).
3) I’ve had successful worm bins without air holes in the lid, but I do recommend you add them since it helps provide more air flow inside your system, and allows more water vapour to escape. This is of course assuming we’re talking about a plastic enclosed bin of some sort.
4) I like creating a layered system when first setting it up, but usually by the time the worms are added (I often like to let my systems age for a little while before I add worms) I will have mixed it up a little to help distribute moisture and aerate everything. Layering certainly isn’t a requirement, and the worms will end up mixing everything up either way.
5) The food can be placed at the top of the bin, but this may increase the likelihood of attracting ‘pest’ organisms like fruit flies. I personally prefer to bury wastes – but not TOO far down.
6) You CAN mix in a little soil when you first set up the system to inoculate it with microbes and to provide some grit for the worms (helps them with digestion), but it’s certainly not a requirement. If you do add it, do so in moderation. Soil can be dense and heavy, thus impeding air flow and may get ‘muddy’ as moisture levels increase. The composting worms certainly don’t need it.
Hope this helps, Tomas – thanks for the questions!