We're so thrilled to be able to share this Q&A with Cathy Nesbitt - worm composting expert extraordinaire, educator, and environmentalist - of Cathy's Crawly Composters.
"Vermicomposting, or worm composting, is an excellent way to convert household garbage into nutrient rich fertilizer. Composting with special composting worms is an efficient and environmentally friendly way to save tonnes of waste from going to landfill." - from Cathy's website
We hope Cathy's enthusiasm inspires some of you to try worm composting to help the earth, reduce waste, boost your soil health as well as your own.
Q: What is so special about worm composting?
A: There are many ways to manage our organic material, a worm bin is simply one way. The very special thing about vermicomposting is it can be done inside. Think about how many people live in condos, townhouses, any place without space for outdoor composting (ha ha or bear country – raccoon nation too). Indoor composting is convenient, looks after our organic matter and offers a tremendous learning opportunity.
Worms are going to play an ever-increasing role in waste management, soil production and therefore food security. It is essential that we learn how. Children learn at an early age how to create soil. When we know how to make soil, we can grow our own food. Composting closes the loop in our food cycle.
Q: How is it different than backyard composting?
A: Regular composting is done outside. Worm composting, ideally indoor, (can be outside Spring-Fall) can be done anywhere without outdoor space to compost or without access to an organic collection program to manage food scraps. Imagine the city of Toronto (6 million people – about 1/2 live in condos, etc.) - all their organic matter goes into the landfill.
Worms are temperature sensitive so 16-28 C (60-80 F) or room temperature is ideal for Red Wigglers. If we are comfortable temperature wise, so are they.
Q: Do I need a specific type of worm for vermicomposting? Where can I purchase them?
A: There are thousands of different varieties of earthworms. Only four have been identified as suitable for worm composting: Red Wigglers, European Nightcrawlers, Perionyx Escavatus and African Nightcrawlers
Red Wigglers are the optimum composting worm especially for the Canadian climate.
Red Wigglers are available online. There are 800-1000 worms in one pound of Red Wiggler Worms. Buyer beware when purchasing from unknown sources.
We sell worms for $60/lb or $40/1/2 lb. You can buy them here.
Q: What set up do you recommend for avid gardeners who are new to worm composting?
A: Any container will do for worm composting. Just like backyard composting, it is important to create the proper environment.
Tower composters offer a few benefits such as managing the moisture and allowing worms to migrate to the next level, no need to handle worms.
We have a simple system called the Living Composter, made in Canada, doubles as a stool and comes in four delightful colours.
Q: How much will I need to feed my worms?
A: Once established and under ideal conditions, Red Wigglers consume about half their weight per day in organic material. The amount of worms will determine the volume of food scraps that can be added.
One pound of worms will convert about 1/2 pound of food scraps per day or 3-4 pounds per week
Q: What different types of bedding material can you use?
A: Worms require a carbon:nitrogen mix. The carbon can be shredded paper, brown leaves, brown grass, straw, cardboard, egg cartons, drink trays, paper towels (without grease or chemical residue). Combine bond paper (white printer paper) with some newspaper as newspaper is more absorbent.
The nitrogen is the food scraps, coffee grounds and manures.
As worms do not have teeth, it is best to chop up both bedding materials and food scraps to increase surface area. This will speed up decomposition and make nutrients available to micro-organisms and worms.
Here is a link to our vermicomposting 101 video and an instruction page for reference in setting up a worm bin.
Q: What happens to my worm bin in the Winter? How do I prevent it from freezing?
A: Worm composting can be done outside Spring-Fall. In Winter it must be brought inside.
It is possible to insulate a worm bin. Air flow is essential so be sure not to create an airtight situation.
Worms in an outdoor pile will breed more than usual in the Fall when they sense the temperature change and deposit eggs or cocoons throughout. They will then hibernate. If the pile freezes, the worms do not survive but eggs will overwinter.
Q: What if I live in an apartment? Can I do worm composting inside? Does it smell?
A: Worm composting is designed for indoor composting and is perfect for apartment dwellers and small spaces. There are many clever systems that fit into smaller living quarters.
Composting is an aerobic process, meaning with oxygen. Worms breathe oxygen through their skin. If the worm bin smells bad, it has become anaerobic. The oxygen has been converted into methane gas. This can easily be corrected. Remove some of the 'rotting' food, add additional dry bedding, gently fluff up the bedding to provide oxygen into the mix.
Q: Do you have to replenish worms every so often or will they breed ?
A: Under ideal conditions (temperature 16-28 C, moisture about 75% humidity, air flow), worms will double in number every 3-5 months.
Q: Is worm compost tea better than worm castings?
A: Compost tea and castings can both be used as a soil amendment to assist plant growth in all stages.
Castings can be stored for long periods of time and remain viable. Castings can be frozen and/or dried and still be viable. Compost tea must be used within 48 hours of brewing. Compost tea cannot be stored in an airtight container as the micro-organisms would consume the oxygen and create anaerobic conditions.
Tea can be applied as a foliar or leaf spray. It is used for pest control as it contains insecticidal properties.
Simply put, compost is great, worm compost is greater! The worms convert material into a more plant available form. Worm castings contain micronutrients, trace elements, and micro-organisms. Water soluble they will not burn plants. However, being super rich, a little goes a long way.
Q: Do worms really have ten hearts?
A: Earthworms have 5 hearts.
Q: I know they're harmless, but worms still kind of creep me out. Do I have to touch them?
A: I was afraid of worms before starting my business. Not that they would harm me, I just thought they were gross. I started to do research about vermicomposting and learned that Red Wigglers convert “garbage” into gold, have 5 hearts each and live up to 10 years, I had a shift and started to really appreciate the role worms play and why we need them.
For those that do not wish to touch the worms, there are tower composters and other systems where worms will self-harvest to the next level.
Q: We talk a lot about nutrient balance for optimum soil and plant health. What is the best, balanced diet for a worm, so that they and their castings are the healthiest?
A: Best advice is to just provide a good mix of carbon and nitrogen, a handful of good soil or compost to add microbes, crushed eggshells to balance pH then let the worms do the rest. We want to micro manage everything. Vermicompost is the most natural process. Patience is required at the beginning of a new worm environment to allow microbes to get established. The worms convert material into a nutrient rich material.
Q: When is the best time to start a worm bin?
A: Fall is the perfect time to start a worm bin. Start in Fall to have nutrient rich soil ready for spring planting. No need to schlep outside to the compost pile during winter.
When schools start a worm bin at the beginning of the school year, the students experience worm composting from set up to harvest. Worms offer a cross curricular learning opportunity.
Thank you so much Cathy for sharing your knowledge of and passion for worms and vermicomposting with our Incredible Seeds community!
Cathy, and her worms, live in Southern Ontario. If you're in Ontario too, be sure to check out Cathy's upcoming events, otherwise check out Cathy's website for more information on getting started with vermicomposting.