Yves here. ZOMG, plastic irrigation pipes are bad enough, given what we now know about microplastics. But plastic mulch? The mind reels. It’s presumably often in direct sunlight, which I assume would accelerate the transport of plastic into the soil.
And yes, it is used in the US (I assume the gardeners in the house will snort at this being news to me). See this article in Science Direct for details.
By Sanket Jain, an award-winning independent journalist and documentary photographer based in Western India’s Maharashtra state. His work has been featured in over 35 publications, including MIT Technology Review, Devex, Wired, Telegraph, Thomson Reuters Foundation, The Nation, British Medical Journal, Verge, USA Today, Progressive Magazine, and others. He has won more than 15 journalism awards. Read his stories at www.sanketjain.in. Originally published at Yale Climate Connections
hen someone asks farmer Naiku Gaikwad about soil pollution in his village, he points to an abandoned 40-foot well filled with plastic.
“After harvesting their crops, farmers here toss hundreds of kilograms of plastic mulch into this well,” said the 69-year-old farmer from Jambhali village in Maharashtra, India.
Farmers started using plastic mulch in this village two decades ago because it provided short-term benefits like earlier harvests, increased water-use efficiency, higher yields, and reduced labor costs.
The mulch is a thin, flexible sheet, usually black- or silver-colored, that farmers spread over the soil like a blanket to suppress weeds, retain moisture, and regulate soil temperature.
Although farmers clear plastic mulch from fields after harvesting, complete removal is often impossible because the mulch tends to tear apart, leaving behind plastic residues. Repeated use leads to a substantial buildup of plastic debris in the soil. Through exposure to sunlight, changing weather conditions, and farming activities, these residues gradually break into microplastics, which are particles smaller than five millimeters.
As microplastics break down in soil, they release climate-warming gases like carbon dioxide and methane by altering soil chemistry and boosting microbial activity. This process contributes to climate change and also harms plants by reducing their ability to perform photosynthesis and absorb carbon dioxide from the atmosphere.
Globally, 4 million tons of plastic mulch are used yearly, with an annual increase of 5.6%, contributing to a buildup of microplastic pollution in soil. A 2016 analysis indicated that around 20 million hectares of agricultural land use plastic mulching.
A long-term study in China found that microplastic levels were 10 times higher in fields with plastic mulch after 32 years than in fields without it. Researchers also found that microplastics migrated to deeper soil layers, making their removal more difficult.
“The plastic pollution legacy will remain in soil for centuries,” the study authors warned.
Researchers have found that on average, contaminated soils contain over 6,000 plastic particles per kilogram. Agroplastics like mulch film are a significant source of plastic pollution, but plastic can also make its way into soils through regular applications of wastewater treatment sludge, which farmers often apply to fields as a fertilizer. Plastic particles migrate into wastewater sludge from everyday items like packaging, synthetic fibers from clothes, and personal care products that enter waterways. Wastewater treatment sludge adds an estimated 63,000–430,000 metric tons of microplastic annually to European agricultural soils alone.
Inorganic fertilizers, which are chemically manufactured nutrients used for boosting plant growth, are also direct sources of microplastic particles. Some have slow or controlled-release coatings, which release nutrients gradually and contain nonbiodegradable polymers that release microplastics into the soil as they degrade.
How Microplastics Contribute to Climate Change
Common plastics like polyethylene or polystyrene release methane and ethylene into the atmosphere when they’re fragmented by ultraviolet rays from the sun, explained Margherita Ferrante, a co-author of a review paper on climate change and environmental microplastics. Ferrante is a specialist in hygiene and preventive medicine and general pathology and a professor at the University of Catania in Italy. The methane can then react with other molecules in the atmosphere to form the heat-trapping gas carbon dioxide, Ferrante said.
Both traditional plastics and biodegradable bioplastics emit climate-warming gases, she added.
Usually, soil stores more carbon in a stable form than the amount stored by the atmosphere and vegetation. But soils can also emit carbon dioxide, a process called soil respiration, which occurs as microbes decompose the organic matter in soil and plant litter.
Without the influence of microplastics, soil doesn’t emit a significant amount of carbon dioxide. However, microplastics in the soil can trigger higher emissions by altering microbial activity and increasing the activity of certain soil enzymes.
A study found that soil containing low-density polyethylene or lightweight plastic, such as plastic bags, increased soil respiration by eight times. The plastic mulch used by farmers is made from polypropylene or polyethylene plastics.
Findings from a 2023 study indicate that when microplastics mix with soil, they modify soil structure, sometimes creating tiny gaps that loosen the soil. This improves air circulation, giving organisms in the soil more oxygen. This helps them break down organic matter faster, releasing more heat-trapping carbon dioxide.
Microplastics can change the soil in ways that backfire on farmers. Study co-author Jin-Yong Lee, a professor of hydrogeology and dean of the Office of Research Affairs at South Korea’s Kangwon National University, explained that microplastics in soil harm beneficial bacteria, change the soil chemistry, and disrupt the nutrient cycles, lowering the availability of nutrients for plants.
And in a study published in March 2025, scientists found that microplastics reduce plants’ and algae’s ability to perform photosynthesis by up to 12%.
Deteriorating Crop Health
In December 2024, Naiku Gaikwad grew 1,800 watermelon plants but couldn’t sell one as a pest infestation killed most of them within eight days. Instead of turning a profit, he lost money on the crop.
“We use plastic mulch to ensure the pathogens don’t reach the roots, and the crops need less water,” he explained.
He believed plastic mulch would protect the crops, but instead, it may have become counterproductive in ways he never imagined.
When Gaikwad inspected his soil, he discovered it was filled with tiny plastics, which he blamed for the loss of his crop.
“Since the soil lacks nutrients, my plants can’t fight pests effectively,” he said.
Farmers struggle Amid a Lack ofRegulations
While plastic mulching has skyrocketed, not everyone in Jambhali has adopted it. Farmer Ashwini Gaikwad (no relation to Naiku Gaikwad), 38, hasn’t used plastic mulching in two decades of farming.
“I always doubted whether they are effective over the long term, as I was worried about their impact on the soil,” she said.
Looking at her neighbors’ results, she feels relieved about her decision.
“I have done everything possible not to introduce plastics into the soil.”
But some farmers believe that using plastic mulch is a necessary trade-off. In those cases, Ferrante suggests using plant fibers or sheets made from natural biological materials. She warns that they should not be bioplastics, as those contain small polymers that may release micro- and nano-plastics over time.
Lee suggests improving waste management systems to prevent microplastics from entering the soil through filtration and recycling practices. And a growing body of research is exploring bioremediation, a natural way to manage microplastics in soil using microorganisms, fungi, and plants. Certain bacteria and fungi form biofilms that help break down microplastics, while plant roots and soil organisms assist in stabilizing or removing them.
Gea Oliveri Conti, associate professor of hygiene and public health at Italy’s University of Catania, said that EU regulations aim to prevent and reduce the impact of certain plastic products that are harmful to the environment and human health and promote a transition to a circular economy with sustainable business models.
But Conti suggests that more regulations are needed worldwide.
“An important tool to minimize climate change is to achieve complete management of plastic waste, increasing the prevention of microplastic dispersion, protecting planetary health, and addressing plastic pollution by preventing virgin plastic production,” she said.
With no regulations and mounting climate disasters, microplastics have become a hazard. Every month, Naiku Gaikwad watches helplessly as more plastic mulch clogs the well and his surroundings.
“The waste you see around has been here for 20 years,” he says with frustration. “One day, it won’t just be in the soil,” he added. “It will be in every corner of the world. And by then, it will be too late.”
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crikey. makes me wonder about the Indian farmed shrimp I’ve bought in the past. (yes, india is a very big place and Maharashtra is hundreds of miles from the shrimp farms in the south)
and yes in this bizarro-world, it is cheaper-easier to buy farmed shrimp from India or Vietnam than wild shrimp from Nova Scotia or Louisiana (if you ignore that whole BP Horizon thing).
This is a tough one. There are no ideal solutions. Weed control is necessary in agriculture. In the old days when everyone grew much of their own food, mechanical weed control was the primary method (good old fashioned pulling weeds by hand- there are some modern mechanized weed pullers, but they are hit and miss, and pulling weeds by hand does not scale) Other methods are herbicidal (we all know the drawbacks here), mulching (mulch is a vector for diseases, especially fungal), tillage (this damages soil biology and increases compaction problems, and also volitalizes soil carbon, causing CO2 realease instead of sequestration), and then you have plastic mulch.
We have a market garden operation, and we use a combination of tillage, hand-pulling, mulching during the drier period in late July through August, and geotextile fabric mulch over conventional mulch (similar to plastic, but much heavier and is reusable for many years. The conventional mulch feeds the soil under the geotec, while the geotec prevents transfer of fungus and other organisms off the crop plants) around high value crops like tomatoes and peppers. We also use heavy Guage drip tape, which is also reusable for many years. Conventional irrigation is a disease vector, and is also very inefficient.
Pretty much every option involves a compromise if you are growing beyond the subsistence level. We try to do our best to minimize harm.
The local Soil & Water Conservation District staff recommended tarping ( plastic mulch) before planting on the acres we have open to cultivation. It’s worked as promoted: kills weeds and makes for easier planting of the rows. I’ve always worried about the amount of plastic used in large-scale ag. As a former backyard gardener, my plastic use was substantially less though plastic containers for plants and soil amendments are profuse, ubiquitous, and non recyclable. We sowed thousands of seeds in our greenhouse and that involved a major use of plastic. Scale that to the mega-mart lawn & garden center and the problem takes on epic proportions.
If only ag could be converted to a permaculture approach of guilds rehydrating the landscape, generating its own nutrients, and producing multiple crops for people, livestock, wildlife, and the community.
Fun fact: a couple of years ago, went to an Amish farm to glean remainder of cabbage harvest for a local food bank. Huge field, probably 5 acres, covered with thick black plastic and massive cabbage heads poking through it; a real plastic mulch! Guess they have no qualms about plastic contamination.
Who in their right minds would have thought that would be a good idea? No wonders hundreds of thousands of American are chronically ill prematurely. With thousands of chemicals commonly used in the Us Big Agriculture banned in Europe? As I have been saying for twenty plus years, the American Farm belt is toxic and laced with dangerous chemicals, many banned in other nations. What did you expect?
I know, right? There’s plastic mulch?
Around here they seem to use this plastic mesh that they’ve put down, not for gardening, but whenever they’ve done minor construction around the lake, on top of straw, to keep the afterwork from getting muddy I guess. Naturally I don’t think anyone ever comes to collect the plastic, which sheds into the environment. What a debacle.
Yves, I think that the reference to “plastic mulch” is specific to India. It actually refers to the plastic sheeting that you see used on farms everywhere.
We recently had a house built for us on undeveloped land. I was shocked by the amount of plastic “road cloth,” “landscape cloth” and sheeting that was used by our contractors. I’d estimate close to ten thousand square feet were used under the structures, the driveway, and the greenhouse. Most of it is buried and has remained stable, but the stuff deteriorates rapidly when exposed to sunlight and the weather.
In the garden and the orchard we’ve adopted no-till sheet-mulching/hugelculture methods using cleared brush and cardboard for weed control with pretty good success. Lord knows we have plenty of cardboard to work with as all our appliances and furniture came from China wrapped in hundreds of pounds of the stuff! Since it’s made from paper it theoretically biodegrades safely.
Cardboard still has glues so although it is paper there is still plenty of petroleum products that get into the soil
make sure to cut off the thermal-paper shipping labels. you never know.
I would also add I was just at the nursery a few days ago, and I noticed they are still selling in huge abundance the “decorative” gravel or mulch that is made out of old tires. It would be one thing I suppose if tires were actually made out of rubber. However, this stuff is basically the same as asphalt.
And yes, there is plastic mulch, but never forget the square miles of landscape “carpeting” that is in every neighborhood in America. The mind reels.
All of our clothes – every last square inch – are all 100% cotton. All of our sheets and pillowcases etc, that she makes herself – 100% cotton. My wife makes T-shirts, pants, denim jeans, all my work clothes, etc. The suits and ties are all 100% wool or silk and also non-petroleum. When these get too old or too many wash cycles – she takes what is salvageable and makes quilts – and every bit of the rest of this is used as weed shields in the landscape – it breaks down over several years – and has to be replaced every once in a while – but it works. It does the job for protecting our food and decorative plants from the weeds around here.
I would add as an aside, earthworms in abundance are your deep friend in the garden – treat them as a treasure.
As I said a few weeks ago, weeding is a huge part of our life. Our house was built over an old hay field – and according to the neighbors, all of the area around us was planted with genetically modified plants that were completely resistant to Round Up. Therefore, it is very difficult to kill. It has to be rooted up – and even then it is very aggressive and just keeps coming up. It seems to be getting stronger and evolving before our eyes. I have no recollection of weeds being this problematic when I was a kid – nor do any of the neighbors around us. In the event of a national emergency, because of all these plants we have planted and chemicals we have used in the country for decades, life for farming in the back yard is going to be orders of magnitude more difficult than our immediate ancestors. You can count on it.
There was a time when mountains of old tyres were dumped on the sea floor supposedly to help stabilize it and establish communities of animals and plants on those artificial reefs. Decades later, as it is unequivocally known that this was not a good idea, fishing out all those tyres represents a titanic task — many of them having been moved farther away by currents, or sunk below the sea floor.
As for mulch: in the 1940s-1950s, coconut fiber was apparently so abundant that it was incorporated into the plaster mass serving to build cheap prefabricated separation walls in Europe (at least in France). Why aren’t there solutions based on such materials? There must be a truly massive amount of such organic fibers — especially in India, where coconuts are plentiful.
I use coconut fiber hanging baskets for the flowers around my house. Much nicer looking than plastic and very durable. Like you, I wonder why the use isn’t more widespread. Same with cardboard CD cases as opposed to plastic ones. Why any company is still using the easily breakable plastic ones is beyond me.
Coconut fibre is called coir and it’s a huge industry now. You can buy it by the bale in garden stores because it’s better than peat, which is a vanishing resource. Accordingly, it’s expensive.
I use rubber between the rows of my veggies. They call it pond liner and I buy it by the roll. I cut up the roll into long pieces about 2 feet wide and roll them up in the fall and leave them at the end of the rows all winter, then roll them out again in the spring in a slightly different configuration so the veggies are growing in a different place each year. The pond liner is heavy and I can walk on it all summer. I can’t get on my knees anymore to weed, so with the rubber I can still garden despite my illnesses.
I have huge colonies of both earthworms and compost worms that live under there and keep the soil friable and nice. I never shovel or till. In the fall when I’ve rolled up the rubber, I fertilize with egg shells and lime and leaves, and fish bone meal and glacial rock dust. Then I bury the kitchen compost all winter in covered holes.
Where exactly can one buy glacial rock dust nowadays? Where specifically by name do you buy your glacial rock dust from?
I grew up in Iowa where there is an abundance of black top soil. I was very surprised to learn the reason for high radon gas in basements there is the soil. It is finely ground rock dust from glaciers and is still emitting radon gas.
You can find glacial rock dust anywhere in the world the glaciers stopped their advance and melted. It’s cheap as dirt and just as plentiful in some areas.
Unfortunately, I don’t have a car and can’t get to places where I could just pick up some glacial rock dust. So I am limited to having to buy it from anyone who sells it and ships by mail or however.
So I was hoping that Ann just up above would know of a source or sources where one could buy some glacial rock dust.
Most of my neighbors in various places have had putting green-like front lawns; manicured and chemical-doused. Never saw Arnold, Jack, Tiger or Rory show up, though.
We decided to not kill any weeds in our yard. We just mow it all and say if it’s green its lawn.
If it’s green enough, it’s lawn enough.
Plastic mulch was pretty much ubiquitous in pineapple cultivation in Hawaii. I live on what was formerly pineapple land (Castle&Cooke aka Dole Pineapple) and shreds of plastic are everywhere in the soil. Even hiking in the mountains you find the stuff.
Hasn’t been seen as an issue that I know of. The main issue historically was the Heptachlor crisis in 1982.
Boy Howdy, if ever there was a reason to have EPR Laws, plastic sheeting (films, sheetings, and geo-techs) are it.
As well as—
“An important tool to minimize climate change is to achieve complete management of plastic waste, increasing the prevention of microplastic dispersion, protecting planetary health, and addressing plastic pollution by preventing virgin plastic production,” she said. -Complete Management-
I’ve seen it with Celery in Hartville O and Broccoli in Arequipa Peru. Around here, on Strawberry beds is the most common app of black sheeting-but other summer vegetables more and more. Lasts maybe?? 3/4 seasons. My CSA uses it.
But there are better fabrics available
Sickening to see acres of it at the landfill before burial. Private profits with socialized costs.
EPR(ExtendedProducerResponsibility) now!!
Also, Nobody should be surprised that their home has a 6mil plastic moisture barrier under their home’s concrete basement/floor/garage slab floor. It’s Code.
I’ve found nothing like it to suppress weeds with low labor input, but I use 5×5 black plastic sheeting for small areas, and canvas tarps for larger. It does break down in sunlight, ask me how I know, so I toss it before it starts to. Waste issue is undeniable.
I got a bunch of cellophane to try as an alternative, we’ll see how that works.
I like Wilkerson’s analysis on these subjects; he’s very knowledgeable and is morally grounded, but he did not aquit himself well by covering for Powell’s astounding moral failure during the run-up to the Iraq war. Powell lied, and knowingly, during his outrageous testimony over the faked “intel” regarding Iraq’s possession of secret labs for the production of weapons of mass destruction (remember that little vial of white powder he brandished?). Wilkerson later said something along the lines of, well, if he wouldn’t have done it, they (Cheney/Bush) would have gotten someone else (say, Condi Rice) to make the lie-filled presentation. That was amazingly cynical. If Powell would have gotten up and instead told the truth and then resigned (Imagine! What a public display of courage and integrity that would have been!), the war might have been stopped. Powell would likely have become a pariah (at least in DC), but he would have been a true hero, and history would have been kind to him, to say the least. I was stunned and angry when Wilkerson made his remarks about Powell, essentially covering for the General’s criminal complicity and duplicity in front of the entire world. We know what happened after that.
But I do like Wilkerson’s studied and very knowledgeable understanding of how the DC War Lunatics think, and operate, and I believe he’s right in his analysis. He’s a good man, and he’s very worried. However, as Mark Sleboda has said, the War lunatics in DC know that Putin is very rational and very cautious, despite the propaganda that many US citizens believe, including the Media.They likely figured they could get away with what amounts to an insane publicity stunt (the first thing I thought of was Kursk). What’s troubling to me is the unnerving indifference to these possibly world-ending acts among the public here. Same as ever.
Here is what Colonel Lang at Sic Semper Tyrannis once had to say about some of Colonel Wilkerson’s criticism of something that Colonel Lang had been criticising years before.
” I do not care what Wilkerson has to say. He came late to the battle.”
A few recent reviews for the scientific minded. Soil plastics enter our food directly, and also influence pollinators and earthworms. Many BigAg organics are grown hydroponically with extensive plastic. Roots can uptake particles up to 2 microns, and the stoma take up smaller particles.
Chen G, Li Y, Liu S, Junaid M, Wang J. Effects of micro(nano)plastics on higher plants and the rhizosphere environment. Sci Total Environ. 2022 Feb 10;807(Pt 1):150841. doi: 10.1016/j.scitotenv.2021.150841. Epub 2021 Oct 8. PMID: 34627902. https://pubmed.ncbi.nlm.nih.gov/34627902/
Lazăr NN, Călmuc M, Milea ȘA, Georgescu PL, Iticescu C. Micro and nano plastics in fruits and vegetables: A review. Heliyon. 2024 Mar 18;10(6):e28291. doi: 10.1016/j.heliyon.2024.e28291. PMID: 38545146; PMCID: PMC10966681.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10966681/#sec3
Symeonides C, Aromataris E, Mulders Y, Dizon J, Stern C, Barker TH, Whitehorn A, Pollock D, Marin T, Dunlop S. An Umbrella Review of Meta-Analyses Evaluating Associations between Human Health and Exposure to Major Classes of Plastic-Associated Chemicals. Ann Glob Health. 2024 Aug 19;90(1):52. doi: 10.5334/aogh.4459. https://pmc.ncbi.nlm.nih.gov/articles/PMC11342836/