How To: Worm Composting

As the weather becomes nicer, and folks are spending more time in their garden, I am hearing more questions about how to start composting with worms. Since I just installed a worm compost bin for Eleanor and David, I thought I would highlight the steps here for anyone else interested in putting together one for their yard.

For those of you who live in San Mateo County, the first step is to visit the RecyleWorks website and order your worm composting unit. The County of San Mateo subsidizes the cost of compost bins for residents. For $29, you are able to purchase a Wriggly Wranch Vermicomposting Bin. Residents may also purchase Smith & Hawkin Biostack Bins for a reduced rate (not suitable for worm composting, but good for general garden composting). If you live outside the county, check your local Public Works departments for similar programs – in Santa Clara County offers recycled worm bins for $10 and Los Angeles County offers worm compost bins with 1/2 lb of worms for $65.

After the bin arrives, unpack carefully and check for information about ordering worms. I have purchased mine from Sonoma Valley Worm Farms, two pounds of worms is $49.50, which includes shipping and tax. Sometimes I have found coupons inside the worm compost box, so be sure to check there first.

Find a good spot for your worm compost bin. Mine is outside, up against the house, near the kitchen door, in a spot that is shady in the afternoon. I have heard folks who have had them in the garage. Inside the house is probably not a good spot.

Make sure you have a bucket, scissors and a nearby water source handy.

Attach the spigot, then the legs of the bin. Soak the block of bedding material in the bucket filled up 1/2 way with warm water. While the bedding soaks, complete the set up of the bin, adding the main tray atop the bottom bin.

After the bedding has soaked for about 15 minutes, squeeze out the excess water and add to the main tray. This will be the place where you add your worms and the vegetable and fruit scraps to feed the worms. Add in the worms, along with whatever dirt came with them. Cover with a layer of torn newspaper that is slightly moist. You will always want to have torn newspaper over the worms, as it will help keep the flies away. I have also had success using shredded bills from my office shredder.

When you want to feed your worms, lift up a corner of the shredded material and sprinkle in the food. Worms like their food in smallish pieces, so give veggie scraps a chop if they are too big. Here is more information on how to feed your worms.

The best product of worm composting is the worm tea, a highly concentrated fertilizer that is completely organic. I dilute with water and use the juice to feed my tomatoes and vegetables all summer. Once a year, I harvest the worm castings and mix that into my raised beds before planting in the spring.