Vermicomposting: Breaking Down Advantages and Disadvantages

Have you come across vermicomposting? If you have, you might be wondering if it would work for you and whether it has advantages over traditional composting. Vermicomposting means using worms to break down organic waste, and it has some great pros, but also some cons. We’re going to look at vermicomposting: comparing advantages and disadvantages.

Some of the biggest pros of vermicomposting include diverting waste from landfill sites, getting rich compost for your garden, being able to compost in a small indoor area, and less loss of nitrogen compared with traditional composting. Some of the cons include that it can be a little more complicated, it requires constant maintenance, and it doesn’t kill weed seeds.

In this article, we will cover everything you need to know about the advantages and disadvantages of vermicomposting.

What Are The Pros Of Vermicomposting?

Kyle Spradley, CC BY-NC 2.0, via Flickr

First, we’ll go through the advantages offered by vermicomposting, and then we’ll move on to the disadvantages you may encounter.

Diverting Waste From Landfill Sites

One of the biggest pros of using a vermicomposter is that it keeps organic waste out of landfills. You may already be aware that organics are a big problem in landfill sites.

There is not enough oxygen for aerobic bacteria to survive, so the waste is broken down by anaerobic bacteria, which produces greenhouse gasses and is not good for the environment.

It is also worth noting that because many countries create vast quantities of organic waste, this is taking up a lot of space in landfill sites, meaning that we have to dedicate more and more space to landfills.

It makes much more sense to try and process the waste ourselves where we can, rather than bury it underground, mixed in with other waste like plastics. Vermicomposting frees up landfill space for other waste, meaning we need fewer landfills overall.

Getting Compost For Your Garden

Your wormery will also produce an amazing almost-compost that you can use in your garden or on your houseplants, or gift to friends if you have no use for it yourself. Vermicomposting produces excellent substrate, and it usually has a higher quantity of nutrients than traditional compost does.

It’s important to note that the soft black earthy stuff produced by a vermicomposter isn’t exactly compost, although it looks much like what you might harvest from your traditional composter. It’s made of very rich worm castings, and it’s full of useful microorganisms.

It can also have a much finer structure, making it an excellent option for planting seedlings or delicate plants. Digging it into clay soils will improve the structure and drainage, and digging it into sandy soils improves water retention. If you do have a garden, vermicomposting can provide an excellent additive.

This is partly because of the ways that the worms break everything down into very fine particles. As they crawl through the food waste and munch different bits, they break up the organic matter and thoroughly aerate it, which makes it better for plants that like good drainage.

The compost from wormeries also contains more nitrates, while traditional compost is usually higher in ammonia. Different plants need different quantities of each, so depending on what you grow, this may or may not be an advantage.

Compact Composting

You might already be aware that vermicomposting is a great solution for those who are lacking in space. If you only have a small garden or no garden at all, vermicomposting is a great way to break down foodstuff and even a bit of garden waste (although vermicomposters can’t deal with a lot of garden waste).

If you live in an apartment and you don’t have a food waste collection service, vermicomposting is probably your only means of keeping food waste out of landfill sites. You can set up a wormery in a surprisingly small amount of space, and it is perfectly easy to keep it indoors, as long as you look after it.

You don’t need to worry about the smell or the worms escaping as long as the wormery is functioning properly and maintained. Of course, these things can go wrong if you aren’t looking after them, but we’ll cover that in the cons list later.

A worm bin can be just a small box in a cupboard, or it can be much bigger. It does not need to be enormously deep because composting worms don’t burrow down far, so many companies create stackable worm bins to take advantage of vertical height.

If you live in a small space with little or no garden, a wormery is an ideal way to handle food waste.

Indoor Composting

Being able to compost indoors ties in with the above option, but has a further advantage: your wormery will continue to operate even when the weather is cold, which an outdoor compost bin may not do.

Because your home is warm, the worms can stay active year-round, and you don’t need to worry about whether food waste is piling up and not getting broken down when the cold weather arrives. You also won’t find yourself trekking across a frosty garden to empty the kitchen caddy!

Being able to compost inside without having to worry about the smell is a definite plus in vermicomposting.

Reduced Nitrogen Loss

Loss of nitrogen can be a frustrating problem because many plans require nitrogen in the soil, and traditional composting often loses nitrogen. Vermicomposting, by contrast, is thought to be able to reduce nitrogen loss by up to twenty percent.

This is key if you are trying to create balanced compost for your garden, especially if you struggle to ensure that nitrogen levels are kept high. While this is definitely getting into the more scientific side of turning food scraps into plant food, it is worth considering as one of the significant advantages of vermicomposting.

Reduced Greenhouse Gasses

Greenhouse gasses are something that few of us think about in terms of our backyard compost heaps, and perhaps rightly so – because composting your waste at home is about as green as it gets. There aren’t really better alternatives, because even the most eco-friendly household will have some food waste and garden waste to get rid of.

However, it is important to consider whether vermicomposting can produce fewer greenhouse gasses than traditional composting. It is thought that it can decrease nitrous oxide emissions and methane emissions, possibly by as much as thirty percent or even more in some places (although methane emissions by only about twenty percent).

This may mean that we move toward vermicomposting as a commercial solution in some situations. More study is needed to understand the environmental advantage of wormeries vs traditional composting, but this is still an enticing start for anyone interested in how they can be even more eco-friendly when dealing with food waste.

Fun For Kids (And Adults)

Vermicomposting has an additional advantage over traditional composting: it is good fun! For children in particular, interested in learning about how food waste works and animal digestion, a wormery is a perfect opportunity to help them understand the cycle of decomposition.

Children will often enjoy the process of feeding the worms and seeing how the waste breaks down over a period of time. The worms will breed and spread throughout the wormery, and children can examine the baby worms and even the worm eggs to get more in touch with nature.

Adults too may enjoy and learn from the wormery. It is quite a fascinating process to watch the worms multiply and fill the bin, and to learn about what they particularly like to eat, and what doesn’t suit their tastes.

Woody materials will take much longer to break down in the wormery, and they will not eat onion skins or onions. Looking at how they break the waste down and turn it into compost-like material is a fascinating experiment for everyone – although the novelty will eventually wear off!

What Are The Cons Of Vermicomposting?

Kyle Spradley, CC BY-NC 2.0, via Flickr

That all sounds great, so now let’s look at the downsides of vermicomposting. What disadvantages do you face when you set up this kind of system?

More Complicated

Different people may disagree about whether a compost bin or a worm bin involves more work, but to a degree, a worm bin is a bit more complicated, if only because the worms need to be looked after so that they don’t die. In an outdoor composter, worms will simply leave if they don’t like the conditions.

In a wormery, you also can’t depend on other creatures breaking down things that the worms don’t like. A traditional composter will decompose onions and other alliums easily enough, but if you put them in your wormery, you will probably find that they hang around for long periods because the worms don’t like the smell.

A vermicomposter also needs to be fed regularly, or the worms will start to get hungry and look for food elsewhere. A traditional compost heap does not need you to keep adding to it regularly, although it will eventually become inactive if you never add new waste.

That means that if you’re going away for a long period, you may need to get somebody to feed the worms, just as you would another pet, and you can’t just leave them as you could an outdoor composter.

Vermicomposting doesn’t need turning as a traditional compost bin does (the worms do the aeration work for you), but it may sometimes need the liquid draining from the tray underneath. This can be a bit of an unpleasant, smelly process.

You also need to keep your vermicomposter at a reasonably stable temperature (worms don’t like to be frozen or cooked) and ensure that they don’t get either too wet or too dry.

Finally, you will have to separate the worms when you want to use the compost. There are all sorts of tips and tricks for doing this, but it can be a bit time-consuming to do. Try feeding your worms on one half of the bin for a few weeks, and then take the compost from the other half.

None of these things take an enormous amount of time, but it is important to keep an eye on all these different conditions and ensure a good balance keeps your worms happy.

Requires Constant Maintenance

As mentioned above, you cannot just leave a wormery alone for months at a time. Worms should be fed about once every one to two weeks, and need to have the tray beneath them checked from time to time.

While a regular composter does need work, it will rarely run into major issues if it is left unattended for a month or two. That said, many people find that wormeries, because they do not need to be turned, require less work overall.

Doesn’t Kill Weed Seeds

A wormery won’t kill weed seeds, whereas a hot composter will. However, traditional compost bins often don’t kill weed seeds either, so this is only a comparison with hot composting.

The worms won’t eat the seeds in most cases, and that means they will be left to germinate in the fresh compost if you add them to your worm bin. If you don’t add garden waste to your vermicomposter, you won’t run into this issue.

Not Capable Of Processing A Lot Of Waste

Vermicomposters are not a solution if you have a lot of waste to deal with. Overfeeding your worms can result in mold, bad smells, and dead worms, so if you are a large family or you have a lot of waste, you may need to build several vermicomposters or use a secondary composting method.

Worms May Escape

If conditions in your bin aren’t ideal, the worms may try to leave it – which could be a major disadvantage if you’re unsure about worms and you have them in your kitchen. However, as long as the bin is kept cool, moist but not sodden, and has food available, the worms should stay put.


Vermicomposting is a great way to deal with food waste and have a bit of fun at the same time. You’ll get some great “super compost” to use on your garden, and divert food waste from landfill sites as well.