Farming without Plastics
by Michael Foley
When I started farming back in Maryland, I based a lot of my organic farming methods on Eliot Coleman’s The New Organic Grower. Somewhere in that book, he presented a back-of-the-envelope calculation comparing the carbon footprint of a head of lettuce grown in California and shipped to the East Coast versus a head of lettuce grown under plastic in his Maine hoophouse. His head of lettuce won hands down.
Coleman convinced me that year-round farming was the way to go. I put up my first hoophouse in 2005 and haven’t looked back. But when we moved to Willits in 2007, it was already clear that Coleman’s calculation couldn’t apply. A Salinas Valley head of lettuce had a lot less miles on it traveling to Willits than those shipping to eastern markets. Still, I built hoophouses and encouraged others to do so. I bought row covers to protect outdoor plants through fall, winter, and spring. I bought shade cloth to protect tender lettuces from the bright California sun. And a couple of years ago, we started buying ground cloth to kill off weeds and prepare the soil for planting.
I already knew plastic was bad for the environment, but I consoled myself that the most common plastics in our farming practice were the least bad: black plastic polyethylene mostly, and polypropylene for the greenhouse plastic and row covers. But plastic turns out to be much worse than I imagined. It is not just another fossil fuel product. It’s a product that pollutes all by itself as it off-gases additives and degrades into tinier and tinier pieces. The scourge of micro-plastics (plastic fragments less than 5mm in length) is becoming clearer, as they turn up in the intestines of fish and wildlife, in our drinking water, and in our own guts. We know that the bigger pieces kill plankton and other small forms of aquatic life, and many of them carry toxic chemicals, from BPA to phthalates, both responsible for a lot of reproductive harm in mammals, including humans.
Bioplastics aren’t necessarily better. Some of them biodegrade, but only under special circumstances—not in your compost heap, garden soil, or the ocean. Some of them don’t. Recycling, in the meantime, is in something of a crisis.
From an environmental perspective, we have to get plastics out of farming. But can we? On the one hand, the answer is, “Of course!” Humans farmed for 10,000 years before the advent of plastic just a few decades ago. We can do so again. On the other hand, this farmer—and I’m sure many others—is finding it hard to break the addiction.
Winter farming without that plastic hoophouse? The French market gardeners of the 18th and 19th century did it, with glass topped cold frames and “hot beds” warmed by composting manure, but it took a lot of labor, glass, and manure. Then there are the “fruit walls,” south-facing walls of cob or brick that absorb the sun’s heat during the day and stave off the cold during the night. Put a glass window in front of the wall and you have the beginnings of a greenhouse.
So there are tools out there that we might adopt and adapt as we try to find our way past the Age of Plastics. The glass greenhouse will be very expensive but last a long time. Other alternatives vary a lot in durability and cost. One of our mainstays at Green Uprising Farm in cooler months is row covers, sheets of spun polypropylene draped over low hoops down each row. Plants get protection from wind and chill, and the ground stays a couple degrees warmer. We’ve experimented using large pieces of cheesecloth and have found that they’re better than plastic. They stay up in the rain and snow, and they seem to last longer than the plastic version. They are also twice the cost.
In hot weather, we depend upon shade cloth. It covers much of our salad garden and our propagation house. This summer I tried the old alternative, used for centuries in farming cultures around the world—reed mats, sold as “reed fencing” here. It only took a few to cover the propagation structure. They’re much cheaper than shade cloth and much more attractive, and they give very effective shade for tender starts and microgreens.
Before market gardeners adopted plastic landscape cloth to kill weeds and prepare soil for working, organic gardeners and permaculturists advocated plain old cardboard. It works, and big pieces can be obtained from your friendly local furniture store. It can be cumbersome and ugly too, and we still have all that landscape cloth, but we’re using both now.
Bigger farmers depend upon sheet plastic mulches to suppress weeds, especially around delicate strawberry plants. But I met one farmer in Monterey County’s strawberry belt who was experimenting with burlap. We’re now trying out burlap to preserve the moisture around slow-germinating carrots, following the advice of Paul and Elizabeth Kaiser at Singing Frogs Farm.
Our old poly seed starting trays are coming apart, and it’s time to think about alternatives. Eliot Coleman introduced soil blockers to the U.S., a clever European device for producing compact “plugs” for seedlings without need for plastic. We’ll be trying them out soon.
As for packaging, we seem to be stuck with bio-plastic bags for our salad greens, but there are lovely cardboard fruit boxes on the market now that work just fine for tomatoes, pears, plums, and apples.
The biggest challenge is irrigation—miles and miles of poly tubing, with plastic fittings of all kinds. Invented to save precious water, it would be hard to part with and will probably be the last to go, if we ever manage to leave behind everything else plastic.
Can we get plastic out of farming? Yes, but we have a long, long way to go to end our dependence!
Michael Foley farms at Green Uprising Farm in Willits with his wife, Sara Grusky, and daughters, Thea Grusky-Foley and Allegra Foley. He is the author of Farming for the Long Haul (Chelsea Green, 2019).
