Spring has sprung! That means it's time to get out in my Bay Area garden and get to work. It's been dormant all winter as although our temperatures are mild enough here to grow peas, favas, cover crops, and cruciferous veggies like broccoli and cabbage and cauliflower, my raised beds simply do not get enough sun hours each day to produce much in the winter.
So this weekend, my two little boys and I will get out there and get dirty. The first step is always enriching the soil. Like most organic gardeners, my enrichment of choice is compost. At my house we have vermicompost, a super rich compost made by our red wriggler worms, and then my lazy composters compost, made of garden scraps, odds and ends food stuffs like last Halloween's pumpkins and the remains of cut flower bouquets and layered, unturned, in a pile behind the house.
The worms are by far the most fun. I intentionally started my composting career with worms so I could teach my kids that worms, and the other little critters who live in the bin and in the garden, are not yucky or scary. They helped me prepare the bin prior to our first wormy delivery from the USPS, and they help me harvest as well. The best part about worms is they can tolerate neglect. Mine guys and gals were fairly heavily neglected when I went back to work. But they always find something to eat and they produce some of the best compost you can use.
You can find worm bins online at many retailers, like compostbins.com or even amazon. Some counties, like mine, even offer partial subsidies for residents towards a worm bin. Check out your local recycle center or waste processing center for potential options.
Setting up your worm bin is easy. Some come equipped with a block of coir, which is shredded coconut husks. This block needs to be soaked in a bucket of water to be pliable enough to break apart. If your bin does not include coir, just grab yourself a stack of newspapers and get to shredding. Some folks suggest lining the bottom of the tray with cardboard. I found that my worms loved cardboard so much that this substrate barely lasted a week. So I just stuck to shredded bedding.
Fill your bin with the shredded newsprint and use a spray bottle to add water as you go. Fill the bin to the top, it will settle out as you add in food and you'll need to add more shredded paper over time so best to start as fluffy as possible.
Order your worms only AFTER you have prepared your bin. Worms arrive alive and usually only 24 to 48 hours after you have ordered them. They need to be removed from their shipping package immediately so having a worm bin already prepped for them is crucial.
Add your worms and then add your food scraps. Food can be added in whole but it breaks down faster if it's in smaller chunks. Lift sections of the bedding and place the food on the bottom of the bin, cover lightly with bedding and spray a bit more water. You want the bedding to be the same level of moisture as a wrung out sponge. As time goes on and your food scraps are turned into vermicompost you'll notice the compost, which resembles large, wet coffee grounds, on the bottom of the tray. Try not to disturb this layer. Just keep adding the food on top and covering with more shredded paper.
Finally, to keep some of the uninvited guests like slugs from having a party in your worm bin, you might want to cover the bedding with layers of whole newspaper, tucking in the sides and then placing the bin cover on top. If you still get unwelcome visitors, just pick them out and you can either relocate them, release them, or like some gardeners, feed them to your turtles or chickens.
Worms will eat any fruit or veggie. They particularly love the cucurbitae family such as melons of all kinds, cucumbers, summer and winter squashes. They tend to not go as crazy for citrus so monitor any citrus you put in the bin and if after a week it is still barely touched you might want to put that into a separate non-worm compost pile. Worms will also eat SMALL quantites of bread and pastas but as a rule I try to keep that stuff out of my bins. Eggs shells are great and actually provide the 'grit' the worms need to process their foods stuff. You can even add a handfull of garden soil if you are vegan and do not consume eggs. It will serve the same end.
Vermicompost is usually ready for harvest 6-8 months after you begin. Just keep checking and when you see the level of the compost rising you may want to move the top bin to the bottom of the stack and set up the second bin as the new top bin. Set it up with fresh bedding just as you did with the first bin. Add some food and cover. The worms wil migrate up from the bottom bin. The first bin will sit and 'cure' under the new bin and you can just keep monitoring it till it looks right to you.
There will still likely be some food scraps even once it is ready for harvest. But that's not a problem. You can simply turn it under your garden soil.
To harvest, I spread out a big tarp and dump out the contents of the bin. I separate the compost into many small piles in pyramid shapes. Then I scrape off the top parts of each pyramid into a container I'll be later carrying to the garden. The reason for this? There will always be worms who preferred to remain in the bin and didn't migrate up to the new food source. I like to rescue them and relocate them to the new bin rather than sacrificing them in the garden. Yes, red wrigglers can of course survive in the garden, but they won't really have a ready food source so it's best to keep them where they do their best work.
Once you've sifted through all your compost and fished out all your worms, you are ready to spread it in your garden. My single worm bin produces enough compost for me to spread a nice, thin layer over the surface of my two 8x4 foot raised beds. I lightly rake it in and I'm ready to plant right away.
So give vermiculture a spin. It's fun, easy, and you can work hard at it or barely at all. As they say, with or without the help of us humans, compost happens!