The Best Worm Composter

What to Look For

Worm composters come in all shapes and sizes so it helps to know which features you will need when narrowing down your choices.

Look for products with UV resistance to stop plastics becoming brittle and if wood is used make sure it is appropriately weather coated.

Design

The three main worm bin designs are:

• Stacking tray systems
• Continuous flow-through bins
• Hanging Bags

Which of those suits your requirements will depend on where you will keep the composter, your local temperature and climate, rainfall and how you want to harvest the worm castings.

What’s the best worm bin design?

1. Continuous flow-through

Continuous flow-through worm bins work by taking advantage of worm’s natural feeding tendencies to help reduce the amount of maintenance needed in between harvests.

Worms tend to feed nearer to the surface and excrete their castings deeper in the earth. Continuous flow-through designs take advantage of this by allowing you to dump your scraps in the top and harvest your castings from an opening near the bottom.

This keeps your worms working at maximum efficiency as they don’t have to go looking all over the bin for food. Instead, they can work closer to their natural behaviours of feeding near the surface where the fresh organic matter lies. As more food is added and more castings are harvested, you will get a “continuous flow” of castings from top to bottom as the worms feed and create more castings.

2. Tray systems

Tray systems are one of the laziest ways to collect worm castings while still being efficient, making them great for beginners.

Setting up your tray system is simple. Load up a tray with your choice bedding, toss in your daily organic scraps and repeat until the tray begins to approach the top. Once your tray reaches the top rim, load up another tray with bedding and place it on top of the previous tray.

Once the worms finish chowing down on the bottom tray, they’ll naturally move their way up to the next tray, leaving you behind a tray full of valuable vermicast.

3. Hanging worm bins

Hanging worm bins work similarly to continuous flow-through systems, just by using a bag instead of the standard continuous flow bin design.

Organic scraps go in the top, and worm castings can be collected from the bottom opening of the bag.

Hanging worm bins are surprisingly convenient for indoor worm farmers since they can be hung on a stand with space for a collection bin underneath. Some models can even hang on the back of a door in case you’re short on space or prefer the extra convenience of running of a smaller worm farm.

4. Outdoor worm bins

Outdoor worm bins can come in several varieties.

Typically, they are segmented into above-ground and below-ground worm bins.

Above-ground worm bins are large bins or flow through designs that are temperature controlled through insulation and depend on the natural heat of the worm composting process to keep the worms warm.

Below-ground worm bins are buried bins that are less prone to temperature swings and maintain similar conditions to what worms are familiar with.

Others dig windrows, known as vermitrenches, which are long trenches dug into the ground. These trenches work just like regular worm farms that contain bedding with scraps continuously added to the top. Windrows have become less popular with more efficient worm bin designs becoming popularised over the years, however some stick to the old-fashioned way of digging vermitrenches and raising worms.

Footprint

You will also want to be mindful of the total size of the footprint of the worm bin. Sizes can vary from 15” x 15” up to almost 30” x 30” so again keep in mind this will affect your decision depending on whether you plan to tuck the composter in the corner of your kitchen or outside in your yard.

Materials

If you are storing the worm bin outside you have to know that it will stand up to the elements. Look for products with UV resistance to stop plastics becoming brittle and if wood is used in the product make sure it is appropriately weather coated.

Indoor vs outdoor

Some composters are designed primarily for outdoor use such as the rugged looking Hungry Bin Continuous Flow-Through Vermicomposter while others are more pleasing to the eye like the Hot Frog Living Composter which was clearly designed with indoor use in mind.

Worm tea collection

Worm tea is the most potent fertilizer that you will harvest from your worm composter. Some products use a spigot or tap to allow easy collection of the liquid while others use a drip tray. Both have their pros and cons which are outlined in the reviews.

Expandable

If this is your first time getting into vermiculture then it’s difficult to estimate how much food waste you will be able to add and how much compost you will get in return. Some worm bins allow expansions sets to be added so if you find yourself running out of space you can always add more.

 

How does Vermicomposting Work?

Vermicomposting starts with certain species of worms such as red wigglers, white worms, and other earthworm species. When these worms are fed organic material such as food scraps, they chow down on your leftovers and turn it into vermicast.

Vermicast is both higher in nutrients and lower in contaminants than the original material, making it a potent compost that makes plants grow like crazy!

All you need to get started is the right worm, some organic food scraps, and a worm bin with bedding.

Worm composting is great for the environment too. Vermicomposting recycles organic matter, preventing it from going to the landfill. Worm composting also helps your local environment by improving the soil, retaining moisture and reducing your plants’ water usage.

How do worms make compost?

Worms make compost by tunnelling through their bin and looking for food. Once they find food, they chow down, and digestion begins.

Worms digest food using “grit” which are sandy particles that break down food through friction. Worms get this grit from the soil, although you can also supplement their grit supply with washed and ground eggshells.

After the food is broken up by the worm’s grit, it moves into their intestine where the worm absorbs some nutrients before expelling worm castings which are discharged into the soil.

These castings are commonly called “black gold” due to their high concentration of good soil bacteria and nutrients. Gardeners also give them the name black gold due to their unique porous shape that increases air and water circulation in the soil, making them perfect for helping plants grow healthier and faster.

From the time you add organic matter to the worm bin to the time it’s ready for harvest can take about three months if you feed your worms daily. A less optimal worm farm will be producing compost up to every six months, meaning your worm to food ratio needs adjusting!

Worm Composting vs Regular Composting

For those interested in making their own compost, the idea of whether they should choose worm composting or traditional composting often comes to mind.

So, which is better, worm composting or regular composting?

It depends on how active you want to be in the composting process and how rich you want your compost to be.

Traditional composting

For regular composting, all you need to get started is a compost bin that to hold your scraps.

Traditional compost tends to smell, so you’ll want your setup outdoors and away from the house. Keep in mind this also means you’ll need to walk further to put your compost into your bin. If it’s freezing cold or blazing hot outside, you’ll want to keep that in mind when placing your compost bin far away from your house.

If you live a neighbourhood, be sure also to put your compost pile somewhere the neighbours won’t complain about the rotting stench. If you don’t have lots of land, you may wish to avoid traditional composting.

Compost bins get hot, which is why you’ll often hear the process referred to as “hot composting.” This heat kills most pathogens and sterilises any seeds or weeds in the compost pile.

Unlike worm compost bins, there are no creatures to aerate the compost for you. You’ll need to stir the compost pile now and then to speed up the composting process and prevent the smell from getting too intense.

Without worms to break down the compost and seed it with nutrients, the end product won’t be nearly as nutrient-rich as the “black gold” worm castings.

For comparison in just how potent worm castings are compared to regular compost, a cubic yard of regular compost goes for about $6 to $30 while a cubic yard of “black gold” worm compost goes for anywhere from $300 to more than $2200!

What are the advantages of vermicomposting?

Vermicomposting, on the other hand, isn’t quite as easy to set up, but once you’ve got everything started it doesn’t take much to keep the black gold flowing!

Opposite of regular composting, worm composting bins don’t produce any odour. No odours mean they can be placed indoors or outdoors, including in small apartments, as opposed to compost bins which should only be placed far away from your house.

While traditional composting requires you to aerate the soil, with vermicomposting your worms will aerate the soil for you, so there’s no need to stir your worm compost bins. Also, the stirring that occurs when you harvest your compost is adequate for aerating and decompressing your bin’s soil.

What are the disadvantages of vermicomposting?

There are a few drawbacks to vermicomposting, but they can be easily managed.

The main disadvantage of vermicomposting is that you can’t dump unlimited scraps into your worm bins. While you can keep throwing scraps onto the pile with traditional composting, doing so with vermicomposting can cause your vermicomposting bins to smell and become too acidic, which can hurt the worm’s skin. This happens because your worms can only eat so much food and the food left lying around in the bin begins to rot.

Vermicomposting also requires an upfront time investment compared to traditional composting. Vermicomposting requires you to procure worm bins, bedding, worms and oversee the operation to produce compost. Comparatively, regular composting can be started just by throwing food scraps in a garbage can sitting in your backyard.

However, the potent “black gold” compost that you get from vermicomposting is worth several times more than standard compost and makes plants grow like crazy.

How to Start a Worm Farm at Home

If you want to know how to make vermicompost at home, there are a few things you’ll need to learn first.

You can’t just start a vermicomposting operation with only one worm! Try the worm density calculator to see how many worms we recommend starting with.

One of the most common questions asked by people wanting to know how to make worm compost is “does worm composting smell”? Under ideal conditions no, worm composting doesn’t smell. If your worm compost smells, you’re either overfeeding the worms or feeding them something they shouldn’t be eating. Now that we’ve answered one of the most asked questions let’s look at everything you need to know about setting up a worm bin.

What are the best worms for composting?

There are many types of worms used in vermicomposting, however starting out you should only be concerned with the question: “what are the best worms for composting”? The vermicomposting community tends to agree that red wigglers are the best worm for composting with redworms coming in a close second. Red wigglers thrive in a compost environment and prefer it to regular soil. Placing red wigglers in their preferred compost environment makes them produce much richer castings than other worms who prefer to feed on regular soil.

How many Red Wigglers do I need?

You can’t just go starting a vermicomposting operation with only one worm! When you’re planning out your worm farm, you need to have a rough estimate for how many scraps you produce daily. Red wigglers eat about one-half of their body weight every day. Plan that for every pound of organic matter you produce daily, you’ll need about two pounds of red wigglers in your worm bin. Try the composting worm density calculator to see how many worms we recommend starting with.

Where can I buy worms for a worm farm?

When it comes time to buy your worms, you have two options. You can either try to track down a local supplier for your worms, or you can buy composting worms online. Whichever route you go down, you’ll probably order your red wigglers by the pound, which typically contains about 1000 worms! Just remember that for every pound of scraps you plan to add daily, you’ll need to order about two pounds of worms.

What’s the best food for a worm farm?

If you’re wondering what to feed to worms, generally worms aren’t too picky. However, there are clear lists of foods worms love and foods you should avoid feeding your worms. Here’s a list of the best scraps for a worm farm:

• Fruits
• Vegetables
• Grains including bread and pasta
• Shredded paper (except bleached white paper)
• Coffee grinds
• Tea bags
• Hair
• Cow/horse manure (NOT manure from household pets such as dogs/cats)
• Aged and dried lawn clippings (fresh clippings can overheat the worms and kill them)

As for what not to feed worms, the exceptions list isn’t too long. Common sense applies when you think about why each item is on the list. Here’s a list of what scraps you shouldn’t feed your worms:

• Salty foods
• Citrus
• Spicy foods
• Oils
• Food with preservative (processed foods)
• Meat and fish
• Dairy
• Foods that are thermally hot/cold (bring to room temperature before adding to the bin)

From the above list, foods that are salty, citrus, spicy or contain preservatives can irritate the worms’ skin and intestinal tracts. Oils, meat, fish and dairy will tend to rot in the bin, increasing soil acidity and creating an unpleasant odour. Foods that are hot or cold can make the worms hot or cold respectively, making them unhappy and potentially killing them. Bonus tip: for faster composting, break down the food into smaller pieces. Your worms will have an easier time digesting it, meaning more compost for you!

What’s the best temperature for a worm farm?

The ideal temperature for a worm farm will be between 60 to 80 degrees Fahrenheit (15 to 27 degree Celsius. Ideally, you should measure your worm farm with a thermometer for accurate readings. If you lack a thermometer, given that 60 to 80 degrees are also the ideal temperature for an indoor space, you can merely touch the bedding to see if it’s too hot or too cold. If you touch the bedding and your hand feels cold, your worms will be cold. If you touch the bedding and your hand feels hot, your worms will be hot.

What’s the best location for a worm farm?

The best location for a worm farm needs to meet a few essential criteria. First, it should be within the ideal temperature range of 60 to 80 degrees Fahrenheit (15 to 27 degrees Celsius). It should ideally be out of direct sunlight, as this can quickly heat the bin to dangerous levels even if the surrounding temperature is within the acceptable range. The location can be either indoors or outdoors since a properly maintained worm farm won’t give off any odour. Second, your worm farm shouldn’t be in an area where it can become saturated with moisture. Keep it sheltered from the rain so that your worms won’t drown if a storm comes through. Third, it must be in a well-ventilated area but sheltered from strong winds. Ventilation is essential to maintaining the correct oxygen levels in the soil for your worms to breathe. However, strong winds can dehydrate the soil and suck away moisture. One easy way to get extra ventilation for your worm bin is to raise it off the ground through a stand or just by putting it up on cinder blocks/bricks so that air can flow through the bottom. Considering all the criteria above, here are a few of the best locations for your worm farm:

• Basement
• Kitchen
• Bathroom
• Garage/shed (if not prone to extreme temperatures)
• Deck/patio (if local climate fits ideal temperatures)

 

What’s the best bedding for a worm farm?

Bedding is the material placed in your worm bin that helps retains moisture and gives your worms a comfy home. Some people confuse bedding with soil, which is not what you want for vermicomposting. Red wigglers prefer a compost environment as opposed to a soil environment, meaning the best soil for composting is some form of bedding material. Proper bedding will have a neutral pH, have no sharp or abrasive materials, have excellent moisture retention and allow oxygen flow. Here are some materials that fit the bill as the best bedding for a worm farm:

• Shredded cardboard
• Shredded paper (expect bleached white paper)
• Shredded newspaper (except coloured ink)
• Aged compost
• Horse/cow manure
• Coconut coir
• Peat moss
• Straw/hay
• Dried leaves and other yard waste
• Wood chips

Worm composting indoors

You’ll notice that a few of the best locations for a worm farm were indoors. Worm composting indoors is becoming more and more common as people in urban areas begin their vermicomposting operations. Even people in rural areas with plenty of land sometimes house their operations indoors. Keeping your worm composting bins indoors is an easy way to maintain ideal temperature, shelter them from the elements, keep away pests and conveniently add your daily scraps. If you’re concerned about odour, it shouldn’t be an issue given you’re not overfeeding your worms or feeding them anything you shouldn’t be eating.

How to apply vermicompost to plants

You’re probably excited to apply some of that vermicompost “black gold” to your plants! That’s what vermicompost is for after all. Before applying, it’s best to know how to apply vermicompost and how much vermicompost to use. There are two main ways to apply vermicompost. The first way to apply vermicompost is to mix it in with your plant soil. Ideally, you should aim to mix vermicompost with the soil at a 1:5 ratio, meaning 1-part worm compost per 5-parts of soil. This is a general benchmark that most people say to start with. However, you can test different ratios yourself to see what works best for your plants. The second way to apply vermicompost is to apply a layer of it to the drip line around your plant. A “drip line” is the circumference around the plant from the longest outward branches. This is the area where water would “drip off” your plant and land on the ground beneath. When you apply compost here, tiny roots in this area soak up retained moisture and extra nutrients supplied by the compost. Test this one out for yourself, and you’ll see your plants grow like crazy!

How to use vermicompost in potted plants

The process of applying vermicompost to potted plants is similar to applying to any other plants. You can mix in vermicompost with your potting soil at a 1:5 ratio to boost your plant’s growth and help retain moisture. Vermicompost can also be applied as a layer on top of your soil to help retain moisture and supply nutrients to the plant’s roots underneath.