Five Gallon Worm Compost
Nov. 12, 2016
Food waste makes up a large part of our daily waste, and ultimately ends up in a landfill. This food will break down and, if chemicals were used in growing it, they will leach into our drinking water. Even organic food waste will leave residual elements that can contaminate water supplies. Composting is a great way to mitigate the leakage of toxins into the earth.
As the food decomposes, it produces greenhouse gases which are bad for the atmosphere. However, when you consider the journey your food has taken to get to your table, wasting it can have a significant carbon footprint. In fact, if the carbon footprint of food waste were a country, it would rank 3rd, behind the US and China. Check out the Food and Agriculture Organization of the United Nations report on food waste and climate change here.
Composting can be done with a variety of methods, including vermiculture. Vermiculture is composting by using worms, usually red wigglers. The worms will eat the food waste and produce castings which accumulate into a nutritious soil that is called “black gold” because of its impressive nutrient content. The worms break down the food much faster than a sitting hot pile of compost would, so it has virtually no smell.
We used two 5 gallon buckets to make our compost system, but one can also be purchased from the city of San Diego. To make the worm bin, follow these instructions:
You will need:
- 2 5-gallon buckets
- 1 lid that will fit on all 3 buckets
- Power drill (or hammer and nail)
- Food scraps
- Red wriggler worms
Preparing the bins:
Bin 1: Drill 1/8 inch holes just below the rim of the bin. This is to allow for air circulation so the worms do not suffocate.
Bin 2: Drill 3/16 inch or smaller holes in the bottom of the bin. Also drill 1/8 inch holes just below the rim of the bin as well.
Lid: Drill 1/8 inch holes in the top of the lid for air circulation. The prevent fruit flies and other bugs, you can drill larger holes and place an old t-shirt or cloth under the lid before closing it to allow for oxygen without pesky bugs getting in.
Filling the bins:
- Bin 1 will be used for the collection of the compost “tea” which can be diluted and used as a nutritional drink for plants.
- In bin 2, place a sheet of newspaper over the holes and moisten with water.
- Then fill about 3-4 inches with shredded newspaper or broken down cardboard and moisten with water again. It should feel as wet as a wrung out sponge.
- Add a few food scraps and the worms to the bin.
- Add another sheet of newspaper on top of the pile to ensure the moisture stays in and that the worms have a dark environment.
- Put on the lid and let the worms go to work.
- Feed worms daily with a small about of food by placing a pile on the wall of the bin, then the next day adding adjacent to the previous pile, working in a circle until you reach the first pile.
- Continue feeding the worms until your bin is full, then let sit for about a month or until the worms have digested the contents.
- Periodically check the bottom bin to ensure the compost tea is not reaching the bottom level of bin 2. If it has, dump out into a new container so the worms do not drown
- Do not over feed the worms. Feed once there is little food scraps remaining. Worms enjoy small portions daily rather than large portions infrequently. Try saving your scraps for a day and feeding at the end rather than feeding at the end of the week.
- Worms can eat half of their weight in food per day, so if you start with 3 pounds of worms you should provide them with 1.5 pounds of food each day.
- Break down or chop up any large food rinds or peels before placing them in the bin so the worms can break them down easier and faster.
- The calcium in egg shells will help to promote mating between the worms.
- Egg shells will also help to neutralize the pH of the compost. Fruit scraps will be acidic so adding egg shells will help keep the pH balanced and the worms healthy.
- DO NOT add citrus fruits (orange, lemon, lime) as the limestone in these fruits will kill the worms.
- If you see moisture building up on the walls or the inside of the lid, wipe down with a paper towel to prevent mold growth.
- The EPA regulates the ink on newspaper and telephone books so these are the best options for use as bedding in your compost bin.
What to feed your worms:
Fruit and veggie scraps*
Coffee grounds (cooled)
Old, stripped cardboard boxes
Used tea bags (staple removed)
*Worms do not like citrus foods, onions, garlic, or potatoes.
What NOT to feed your worms: