By Susi Torre-Bueno, for Let’s Talk Plants! May 2022.
I've tried many composting methods over many years of gardening, but in late 2021 I came up with this method as the easiest one yet, and it has worked really well for me. What I like best about it is that there is no turning of the compost, no chopping up materials so they're small, no need for any special equipment, and no strenuous effort. In about two months you get gorgeous compost and a fine handful of happy worms, both of which your garden will appreciate.
I save all my kitchen scraps (fruit peels & cores, veggie peels and ends, herb stems, coffee grounds, tea bags, and crushed eggshells) in those flimsy plastic bags you get at the supermarket vegetable aisle. If I have something really large, like the outer part of a watermelon or pineapple, I'll cut that into slightly smaller pieces, but otherwise I don't bother. If I have a flower arrangement I toss in the spent flowers, space permitting, or I save them in another bag to add to the compost. It takes our family of three a few days to fill one bag. You can keep the bag in the freezer and fill it as you go, or you can keep it covered on the kitchen counter. I keep it conveniently on my counter, and I only use the freezer if I don't have time to make the compost right away.
Your compost is made by layering materials in a 5-gallon nursery pot, adding a few worms, moistening the pot, and walking away for 2 months. During those sixty days you'll sprinkle the pot every few days (if it doesn't rain) and keep it covered so that critters can't get into it. Once the time is up, you'll be impressed with the results. I try to make one pot of compost every few days, so there is always one ready to use in the garden.
First, take a five-gallon size nursery pot and add about two-three inches of compostable material at the bottom to prevent the soil from running out the bottom holes. I use dead leaves, shredded toilet paper holders (or other shredded cardboard, shredded unprinted paper, or torn up egg cartons), spent flowers (without seeds), weeds (without seeds or roots), or something similar.
Second, put in about one inch of garden soil, old potting soil, or just plain dirt to your pot. On top of this put the contents of your plastic bag of kitchen scraps; one bag should just fit nicely with a few inches left on top. If you're using frozen scraps, let them thaw a bit so they fit the pot without a lot of empty space around the block of frozen scraps.
Third, add enough soil/dirt to cover the scraps about one to two inches deep - this is so that there isn't any smell. If there is room, put some shredded cardboard on top of this.
Fourth, add about ten to twelve worms from your garden. When I first started composting with worms, I had to dig over a dozen holes all over the garden just to get eight to ten worms to get going. Hopefully, you've got more worms now than I did then.
Fifth, add a label with the date. I cut up old white plastic yogurt containers and write the date with an indelible marker, but you can use whatever is convenient, and re-use the label as well. It's important to add the date so you know when your wait for compost is up. I've experimented with checking the compost after six weeks, but usually there is still some stuff that the worms haven't eaten and it smells pretty bad. After seven weeks there isn't much uneaten, but it still doesn't smell great. At two months it is essentially all turned into compost and smells lovely, plus the nursery pot has dozens of worms. I took five bags of scraps from the freezer in mid-April and made that into five pots of compost. Just one finished pot of compost had more than enough worms in it to add at least a dozen worms to each of the new pots and still add a bunch of worms back into the garden.
Sixth, moisten the nursery pot and put it in your compost area. I use an old raised bed and keep the pots neatly in order with the oldest at one end so it is easy for me to know what compost is ready to harvest. To keep skunks, raccoons and other critters out (as much as possible) I cover the pots with those black lattice plastic flats they give away at the nursery, and weight down the flats with whatever is handy to keep them in place. I have an old gate from a chain-link fence and that covers about a quarter of the raised bed and goes on top of nine nursery pots. Whatever you use, you need to let in air (so no plastic tarp, for example) and be able to water the pots. Finally, a couple of times a week I sprinkle the pots with a hose to make it moist enough to keep the worms happy. I've got some veggies growing in five-gallon size pots, and I just put a few of those pots on top of the black plastic nursery flats, so it'll be simpler for me to keep everything moist enough and contained in a small area. That's it! I've been really delighted with the result, the pots aren't too heavy or bulky for me to manage easily, and I can harvest compost every few days, depending on how often I make new compost. I've been using the worms to start new compost and adding the finished compost (and remaining worms) on top of the soil around my fruit trees and elsewhere in the garden. Once I finish adding compost to my fruit trees I'll be adding it back into the veggie beds to keep my tomatoes happy.
Susi Torre-Bueno served as the San Diego Horticultural Society president from 2003 to 2010 and was instrumental in growing the organization and establishing it as a San Diego institution. In 2012, Susi was honored SDHS Horticulturist of the Year. She lives and gardens in Vista, California.