Vermicomposting

vermicompostingIs your kitchen trash smelling stinky? Do you have an overflowing pile of papers in your recycling that never seem to disappear? As it turns out, food scraps and scrap paper make up a full third of the garbage that the average American household makes daily. Piling all this material into your garbage bin fills up landfills fast! Thankfully there is a smarter (and way more fun!) way to deal with all this garbage: vermicomposting!

If you’ve never considered relying on worms to turn your trash into a nutrient rich soil amendment, read on to learn how easy it is to start vermicomposting right at home.

What Is Vermicomposting?

By definition, vermicomposting is the process of turning biodegradable waste into a high quality compost. This is done by getting it to travel through the digestive systems of worms. Thankfully, worms are willing participants in this. Plus, they’re perfectly happy to eat half their body weight in food scraps every single day.

Feeding your food scraps to worms is a far faster way to break them down than letting the scraps sit in your compost pile. Best of all, worm feces (commonly called ‘castings’) is flush with nutritional value. Thus, leaving soil that has gone through the gut of a worm is five times richer in nitrogen, seven times richer in phosphate, ten times richer in potassium and full of three times as much magnesium as before. The enzymes in worm castings also contain beneficial microbes. These microbes speed up the food web in the soil, which helps your plants grow fast and healthy.

How Does It Work?

Making your own vermicompost is a simple process. All you need is a system of stacking aerated containers (often with holes in the bottom to let worms travel through them), a few thousand worms, plenty of bedding material and a steady supply of scrumptious food scraps. By placing your kitchen scraps in the top layer, you’ll encourage your worms to stay near the surface and chow through their food supply, creating high quality castings in the process.

Once one layer starts getting full of castings, you can place a second layer on top and treat that one as the new feeding tray. In this way, castings are harvested from the bottom of the bin. Therefore, freeing these layers to become the next top feeding trays.

Best Commercial Worms Bins

The easiest way to start vermicomposting is to buy a high quality worm bin from a reputable company. The three companies listed below all produce excellent worm bins that consistently get rave reviews from the people that use them.

Making Your Own Worm Bin

Putting together your own worm bin can be as simple or as complicated as you choose to make it. The most basic form of worm bin requires two plastic bins that fit inside each other. Furthermore, each should be equipped with small holes in the bottom so that excess liquid can drain out into the second bin. To ensure there is room in your bin for this to happen, add spacers to the bottom like small scraps of wood or anything else you have lying around.

Additionally, a lid is only needed for the smaller interior bin, but make sure to punch holes in it. This will ensure that air can circulate through your system. Allowing some airflow also helps prevent the bin from smelling, which is essential if you keep it indoors. Make sure, however, that the holes are small enough that the worms can’t escape out of them.

For more detailed instructions on how to make your own worm bin, follow this tutorial.

Getting Worms

There are more types of worms on this planet than you can count, but not all of them do well in a vermicomposting system. While it may be tempting to dig through your garden bed and pull out some earthworms, these big guys aren’t designed to live in such shallow soil. Furthermore, the conditions of your worm bin will only stress them out. In contrast, red wrigglers (Eisenia foetida) are ideal for worm bins. Not only are they voracious eaters, red wrigglers also thrive in the top few inches of leaf litter in the forest and have no complaints with being confined to a bin. Though it’s possible to collect your own worms through digging around your garden, most people find it more efficient to simply buy them in bulk.

To buy your worms, check out local bait shops, the advertisements in gardening and fishing magazines, or online retailers like Uncle Jim’s Worm Farm. You can also source your worms from local farmers using www.findworms.com to aid your search.

When you buy your worms, make sure you get the right amount for your bin. In most cases it’s best to start with about one pound (800-1,000) red wrigglers. This provides you with plenty of potential mates for all your worms, ensuring that they will soon amp up the population to full capacity.

Preparing the Worm Bin

It’s important to have your worm bin completely set up before the worms arrive. The bottom tray of your bin is the base of the system and needs to contain a thick layer of bedding that is able to let moisture drain through. Additionally, it should allow air to circulate in order to provide the worms with a healthy place to live and breed. There are plenty of material that you can use as bedding, but some of the most popular options are listed below.

  • Shredded corrugated cardboard
  • Shredded paper like newspaper or printer paper (ink isn’t a problem for worms)
  • Peat moss
  • Commercial worm bedding (usually expensive)

The amount of bedding you need depends on the size of your worm bin. A good estimate is to plan on filling the bottom bin layer up 2/3 with fluffed up bedding. Although, you should feel free to experiment to see what your worms respond best to. Make this material 75% moist in order to match the moisture levels of a worm’s skin. A too wet or too dry environment will stress your worms and make it difficult for them to breathe.

You can add a few cupfuls of garden soil into the bedding before your worms arrive in order to inoculate it and add some beneficial microbes into the system to aid your worms.

Preparing a Feeding Tray

The feeding tray is the top bin of your worm bin and the only place that you ever add food scraps. When you first start, add two sheets of dry newspaper to the bottom of the tray (this is just for the first tray, not the ones you add later on). Add a small layer of moist bedding across the paper in order to give the worms to travel. Finally, in one corner add 2-3 cups of food scraps to your bin.

Not all kitchen scraps are appropriate for a worm bin. Acceptable food scraps include fruits and vegetables, coffee grounds, tea bags, pasta and grain products. Things that shouldn’t ever be added to a worm bin include any form of animal product, anything coated in vinegar or heavy sauces, and citrus. These products are too hard for worms to digest and slow down the entire system.

Place a layer of moistened newspaper on top of the feeding tray and plan to add equal parts food scraps and bedding for subsequent feedings. When the right ratio of food to bedding scraps are used, worm bins shouldn’t have any noticeable odor.

Adding Worms

Once you’re ready to add your worms, you can place them and any bedding material they came with right on top of the wet newspapers on the top of the feeding tray. Travel stresses worms out, so expect it to take at least a week for them to settle down enough to get really hungry. In order to prevent them from trying to escape from the bin in the first few days, shine a bright light on the top of the open bin. This will cause the worms to burrow deeper in order to get away.

Adding Additional Trays

Once your worms have adjusted to their new home, you can add food scraps and bedding whenever the levels in the top bin start to get low. After the first tray is full of castings and partially digested scraps, it’s time to add a second tray to the system. Choose one that is stack-able with the first one and fill it with shredded bedding material. Add a few cups of food and cover the top with wet newspapers. Within a few days, the worms should migrate up through the holes in the bottom of the newest bin towards the food scraps. From now on, keep adding food scraps only to this top bin.

Harvesting Your Vermicompost

As your system gets in full swing, you will continue to add feeding trays to the top of your bin, leaving the bottom processing layers full of a blend of nutrient rich worm castings and decomposed organic material. After about 3-4 months, the bottom layers should be thoroughly processed and ready to be harvested. You’ll know it’s ready when you see black soil and small, crumbly chunks of bedding and food scraps.

To harvest this vermicompost, pull all the trays off the bottom tray, keeping them stacked in the proper order. Grab the bottom bin out and re-stack the bins, putting the bottom bin on the very top. Leave the lid off for at least a day to encourage any worms in the layer to migrate down to the lower feeding trays. Once you’re confident that all the worms are gone, you can scoop out the vermicompost and store it until you’re ready to use it. The bottom bin can then be filled with food scraps and become the new feeding layer

Using Your Finished Vermicompost

The nutrients contained within vermicompost make it an ideal soil additive for your garden and potted plants. You can use worm castings just like you would any other fertilizer, as they won’t burn plants. Simply work the castings into the soil before planting transplants or incorporate them into your potting soil for a beneficial boost for starting seeds. It’s also a good idea to regularly top dress your plants with worm castings throughout the growing season. This will provide them with a boost of nutrition and strengthen them against pests and disease. A little vermicompost will go a long ways, so don’t be afraid to use it sparingly at first.

Making Compost Tea

Another way to get a big benefit out of vermicomposting is to turn it into a microbial rich compost tea. Making a tea out of your castings helps the benefits go farther. Even more so, compost tea has been shown to increase the nutritional quality of garden vegetables while helping them grow bigger and more robust. A regular spray of compost tea on plant leaves also helps plants fend off disease and breaks down toxins. Best of all, making compost tea is even easier than maintaining a worm bin.

Simply mix two cups of worm castings into a stocking hose and close the opening. Place the stocking in a bucket of rainwater and add two tbsp of molasses to the mix. Let the mixture soak for at least 24 hours, stirring it occasionally to fully diffuse the worm castings. Once brewed, you can use your compost tea as a foliage spray for every plant that needs an extra boost.




Additional Tips and Tricks

Though setting up a worm bin is a fairly simple process, there are plenty of ways where you can go wrong. There’s no shame if your first attempt isn’t a success. Simply look through these extra tips for advice on how to do better for the next time.

  • It’s normal for other creatures to start living in your worm bin once you get it established. This is especially true if you keep your bin outside. Most of these squatters include sowbugs and pillbugs, springtails and millipedes and won’t cause any harm. However, some pests like centipedes, predatory mites, ants and fruit flies can cause problems. The best way to get rid of these intruders is through non lethal traps specially targeted towards ants or fruit flies.
  • If you are naturally allergic to molds and mildews, keep your bin outside and away from your living space in order to keep yourself healthy.
  • Never put trash like plastic bags, rubber bands, bottle caps, glass or aluminum foil into your worm bin. Not only is it impossible for worms to break down these products, they can also cause harm to your garden plants later on.
  • Keep cats away from your worm bin, lest you want it to turn into giant litter box!
  • Never add fresh animal manure to your worm bin. The heavy amounts of nitrogen in these materials will heat up your compost so much you risk cooking your worms.