Vermicomposting: How to Start Worm Farming

by Matt Gibson

Worm composting, or vermicomposting, is a great way to recycle your kitchen trash while creating a microorganism-friendly and nutrient-rich soil for your garden that is almost completely made up of worm castings. Not only will you be making your garden more luscious and vibrant, but you’ll no longer have to deal with stinky garbage bins now that you are repurposing your kitchen waste. The only kitchen scraps that don’t go in the compost bins are waste from animal products, such as meat and dairy products.

There are many commercial worm farm setups available for purchase that are already assembled and ready to use if you don’t feel like being thrifty, but building your own worm farm system is surprisingly easy and cheap. Here’s a list of all the supplies you will need to get started.

Vermicomposting Supplies

Two large plastic bins of equal size: Shoot for a large surface area and at least 12 to 18 inches of depth when selecting bins.

Worms: One pound of red wigglers should be more than enough to get you started. They reproduce and regulate their own population based on available food sourcing, so you don’t have to worry about adding or subtracting worms.

A drill: Any old drill will do for drilling holes in the plastic bins. If you don’t have a drill handy, some screws, a screwdriver, and a little elbow grease will suffice.

A small flowerpot or brick

Old newspapers and dried leaves: Avoid using colored ink pages as they have toxic chemicals in them that could hurt the worms.

Water

A container for household food waste

What Size Bins Will I Need?

Though vermicomposting is not an exact science, there is a method to the madness when it comes to selecting the appropriate size of bins for your household. Keep track of the amount of kitchen waste you go through for a couple of weeks in your home.

Use a small can or bucket to collect potato peels, eggshells, leftover vegetables, greens, bread, coffee grounds, and any other food waste that you create in your household that isn’t an animal product. Weigh the container to get an average amount of food waste that you go through in a week, and then you will be able to approximate the size of the containers you will need for your worm farm.

You will need about one square foot of surface area for each pound of garbage that you feed to your worms each week. A bin eight inches by two feet by two feet, for example, will accommodate four pounds of food waste per week, which is just about perfect for a one- or two-person household. Larger families will need a larger worm farm. A box one feet by two feet by three feet will accommodate six to six and a half pounds of waste.

Red wigglers are more comfortable near the surface area and not usually accustomed to burrowing deep down to search for food, so a shallow bin with a large surface area is much more preferable than a deep, tall bin.

Step 1: Make the Worm Bins

Drill about 20 holes into the bottom of one bin and about 10 to 15 holes in the lid of the same bin. Leave the other bin the way it is. In the undrilled bin, place the flowerpot or brick in the bottom of the bin, and put the drilled bin on top so that there is some space underneath for drainage.

Step 2: Prepare the Bedding

Lay out a nice layer of torn newspaper scraps and dried leaves, and wet them down with water. The consistency should be moist but fluffy, kind of like a wet sponge.

Step 3: Add in the Worm Food

Layer in worm food underneath a few layers of bedding. A nice mix of kitchen scraps is best. Just be sure to avoid animal products, such as meat, bones, and dairy, as well as any oily waste. Fruit and vegetable scraps work great, as do citrus peels and coffee grounds.

The key to feeding your worms best is balance. If there are too many citrus scraps and coffee grounds and not enough other waste, the mix will be too acidic. If there is too much other stuff, the mix will not be acidic enough. To avoid unpleasant smells, be sure to bury the food scraps underneath layers of bedding instead of just throwing it on the top of the bin. 

Step 4: Add in the Worms

Now that your bins are ready, and the bedding is in place, and you’ve added in a bit of food for the worms to eat, it’s time to add the red wigglers to the mix so that they can adjust to their new home. The worms are attracted to dark areas, so they will naturally dig under the first few layers of bedding and find the food right off the bat.

Step 5: Secure the Perimeter

Worms don’t really want to get out of a dark, wet area with plenty of food supply, but there’s no reason to take chances. A little extra work will make them feel more secure and give them less of a chance of escaping. Just a few layers of wet newspaper placed flat on the top of the bedding will also deter fruit flies from joining in with the worms and infesting the bins. For good measure, roll up a few sheets of wet newspaper, and tuck them into the sides and corners to secure the bin from invaders and escape artists.

Step 6: Making Compost

Don’t expect your worms to recover from the move and begin making tons of compost overnight—or even in the first few weeks. It takes a while to adjust to a new environment. However, after the first couple of weeks have passed, it’s time to start cranking out some compost, and you can really start to put your worm farm to work.

If you put in about one pound of worms, you can expect them to consume their body weight in food waste per day, so you can add in about one pound of food scraps every day. Don’t worry if you are a little over or short, as worms will adjust their own population based on the food source available. If there is an abundance of food scraps, they will reproduce. If there is a shortage, they will dissipate in numbers.  

Step 7: Using The Compost

Now that you’ve put your worms to work eating and repurposing your kitchen waste, it’s time to reap the benefits of your harvest. What’s left in the bin, aside from your worms and their bedding, is a mixture of worm castings, humus, and decomposing matter called vermicompost. This stuff is nutrient-rich and chock-full of microorganisms that can make your garden thrive, so use it sparingly, and spread the love around.

A quarter-inch layer of vermicompost can be added to the topsoil of your houseplants to give them a nutrient blast to keep them looking healthy and feeling on top of the world. Mix the vermicompost in with potting soil mixtures to give your soil a added kick of nutrients to help new plants adjust to their new environments. You can also sprinkle it into seed rows or throw a couple of fistfuls into holes where you are transplanting crops.

Vermicompost is also a great top dresser for mature plants. Just add a handful around the base of the plants on the top of the soil for a nutrient boost prior to harvesting time.

You can also make worm cast tea for watering your garden with to give your whole garden a healthy dose of nutrients and microorganisms while hydrating with a super plant tonic at the same time. Just mix up a gallon of water, a spoonful of molasses, and a pint of worm castings, and stir often for 24 to 48 hours. Dilute this concentrated mixture at one part tea to four parts water, and use it to water your indoor and outdoor plants.

Time is of the essence, however, when it comes to compost tea. You will want to use the entire batch within about a week’s time, or it will go bad and the microorganisms will die before they have a chance to give your garden a nutritious blast.

So, why go through the trouble of starting a worm farm in your home? Well, once the process has started, there’s really not that much work that goes into it. The worms do all the work for you, as long as you give them a healthy environment and plenty of food waste to munch on. The system also saves you a lot of time and effort taking out the trash and saves you the annoyance of dealing with pungent garbage smells from decomposing food waste.

Plus, once you’ve seen the results of what the end product can do for your garden, you will know that all the effort and time that you put into starting your own vermicomposting system was worth every penny you spent and every second you put into it. There’s nothing more rewarding than having the best looking garden on your street, and a couple of pounds of red wigglers and some elbow grease is all you need to give you a leg up on all your neighbors.

Want to learn more about worm composting?

EPA covers How to Maintain Indoor Worm Composting Bin

Mother Earth News covers How to Make a Worm Bin

Mother Earth News covers Guide to Vermicomposting

Modern Farmer covers How to Build a Worm Farm

Planet Natural covers Indoor Composting with Vermicomposting