Yves here. With Hair Furore pre-inauguration furor getting more intense, perhaps another break from reguar programming is in order. However, to be a stickler, “forgotten farming technique” is clearly a misnomer since the central figure in this article remembered it!
As do some of our readers. lyman alpha blob discussed the limits of marigolds last August:
I had been planting marigolds for years around my gardens since they are supposed to repel insects and animals too. And they probably do. But after a few years, I noticed my marigolds slowly being eaten away every single year. Turns out that marigolds are an earwig’s favorite food, so I had likely been inadvertently breeding them for many years. I discovered they also love bok choi and the first small leaves on bean plants.
If anyone knows how to get rid of earwigs other than by going outside at night with a flashlight and squashing them like a crazy person, well, I’m all ears.
By Sanket Jain, an award-winning independent journalist and documentary photographer based in Western India’s Maharashtra state. Originally published at Yale Climate Connections
Farmer Rafik Danwade had been pumping more pesticides on his acre-long field in Jambhali village in India’s Maharashtra state, but the chemicals were getting less effective at protecting his 3,200 chili plants from nematodes and other bugs. So Danwade, 56, turned to a practice his grandfather taught him in the 1970s: He planted 1,000 marigolds on the border and alternating rows of the field.
“Sometimes you must look into the past to find solutions for the present and future problems,” Danwade said.
He and other farmers around the world are relearning the ancient wisdom of sowing plants known as trap crops to protect their harvests from pests. The lessons must be relearned now because climate change has raised temperatures and humidity, leading to increased pest attacks in many regions of the globe.
Marigolds produce compounds that suppress the root-knot nematodes, killing the pests that enter their root systems or contact soil containing a marigold’s bioactive compounds. The bright yellow and orange flowers also release compounds that deter aphids and whiteflies. For Danwade, marigolds also act as a natural barrier, confusing pests looking for his chili plants. Experiments conducted between 1990 and 1993 in India found that African marigolds also effectively managed the cotton bollworm pest on tomatoes.
The eco-friendly method vastly reduces the need for pesticide use at a time when several parts of India and the world have reported increased pest attacks. This method is much healthier for farmers working the fields, people consuming the crops, and soil quality.
Global warming could expand the geographic range of pests, increase the number of generations, and make it easier for invasive insect species to survive the winter season. Pests already destroy 20% to 40% of crop production worldwide every year. According to the U.N.’s Food and Agriculture Organization, insect attacks cause a loss of $70 billionannually, while plant diseases cause a staggering loss of $220 billion. Trap crops could lower these losses while reducing the need to use excess chemical pesticides, which in addition to harming health, also contribute to climate change.
A Global Trend
Trap crops are helping farmers all over the world. In Italy, a two-year study found that Brassicaceae (mustard family) trap crops helped reduce the damage caused to sugar beets by flea beetles. Another paper found that broccoli yield was high when cultivated with diverse trap crops. A Chinese study found that using maize as a trap crop helped reduce the intensity of whiteflies on cotton.
“Trap cropping offers an environmentally friendly alternative to chemical controls by manipulating pest behavior and reducing reliance on pesticides,” said Shovon Chandra Sarkar, a research fellow at Australia’s Murdoch University who coauthored a paper on trap crops published in the Journal Insects in 2018.
Many trap crops protect the main crop by creating “hot spots” where pests are attracted to specific areas, making it easier for helpful insects to find and attack them, he explained. The paper contrasted the effectiveness of trap cropping to insecticides, which are more harmful, more expensive, and often ineffective due to growing pest resistance.
Sorghum is an effective trap crop in cotton fields, and black mustard in sweet corn farms reduced kernel injury by 22%. The authors also suggest that a trap crop should ideally attract at least twice as many pests as the main crop during the vulnerability stage and shouldn’t cover more than 2%-10% of the crop area.
Over the last decade, Danwade said he has witnessed severe changes in climate patterns.
“Rains have become infrequent, followed by a rise in humidity and heat, a perfect breeding ground for pests,” he said. He recalled learning about trap crops from his grandfather, the late Muhammad Danwade, when he roamed the fields as a child, and the traditional knowledge has served him well.
In recent decades, farmers turned to the convenience of chemical pesticides. Globally, pesticide use has doubled since 1990, reaching a staggering 3.69 million metric tons in 2022. Yet rising pesticide use has increased production costs for farmers while hurting their health. Some 385 million cases of pesticide poisoning occur every year, leading to 11,000 mortalities. Of this, 44% of farmers are poisoned by pesticides yearly, with the highest number of cases in South Asia.
Trap cropping has given Danwade a sustainable way to protect his chilies and boost his profits. Marigolds not only deter pests; they also attract bees and other pollinators that aid chili production.
He also sells marigolds, which are essential for daily prayers and decorative garlands in India.
“Because of marigolds, I have seen an increase in chili harvest … adding to the profits,” he said.
Among Danwade’s neighbors in Jambhali village, farmer Shailaja Gaikwad, 45, battled pest attacks on sorghum in 2022 by following her father-in-law’s advice of cultivating hyacinth bean or Indian bean as a trap crop.
“I thought I would end up losing all the sorghum, but to my surprise, everything remained safe,” she said.
This success reduced her cost of production as she did not spray pesticides even once. Before this, Gaikwad lost a considerable part of her soybean, peanut, and leafy vegetables to pest attacks.
“Even if the pests eat all the hyacinth beans, we can still earn money as the entire sorghum remains safe,” she said.
Timing Is Crucial
A government report pointed out that 23 states in India witnessed pest attacks between 2015-2016 and 2021-2022, and trap crops are an important part of the response to these challenges.
Farmers typically use green and black gram or hyacinth beans as trap crops for sorghum, while pigeon peas and hyacinth beans are favored for peanuts. Trap crops such as finger millet or moth bean are commonly used for rice.
“There are several such combinations which farmers used earlier,” Gaikwad said.
A review study published in Applied Soil Ecology in 2019 looked at potential trap crops for reducing the risk from a species of plant-parasitic nematode that causes significant damage to a variety of crops globally. In Northern Europe, yield losses are as high as 40-80% for vegetables like carrots, lettuce, onion, and sugar beet. The study said that trap crops like fodder radish can reduce the nematode populations when mulched early, a process in which the trap crops are cut before the pests trapped in the roots start reproducing.
Timing plays a crucial role in trap cropping. Field trials have shown that if legume-grass cover crops are planted in autumn and mulched in late spring or early summer, they help reduce the nematode population by up to 90%. However, a delay in planting or mulching can increase the nematode numbers as they reach the temperature threshold and proliferate. Moreover, legumes also provide additional benefits by enriching the soil with nitrogen, which helps boost soil fertility.
“The main challenges in designing knowledge-intensive trap cropping systems include understanding pest behavior, optimizing plant species selection, and integrating these systems into existing farming practices,” Sarkar said.
Effective trap cropping, he said, requires a deep knowledge of pest-host interactions, the chemical ecology of attractant compounds, and habitat manipulation techniques. To address this, he suggested identifying supplementary food, the color of trap crops, and attractant chemicals to develop reliable attractants for pests and their natural enemies. What’s also essential is “establishing partnerships with government and research organizations can ensure adequate support for farmers to integrate these strategies,” he added.
Many farmers in Jambhali and several other villages, especially the younger ones, are reluctant to use trap crops and are sticking to pesticides, hoping to maximize yields of a single crop without having to devote space to the trap crop. But Danwade said his sons Yunus, 35, and Shahid, 30, trust trap cropping.
“I am not sure for how long they will continue this practice, but as of now, they are convinced of its results,” he said with a smile.
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Trap-cropping is a form of interplanting, practiced by every small farmer in the world. (I wrote my dissertation about a group of Black peasant farmers in Grenada who revived a tradition of interplanting sugar can with both “provision” (basic food) and “cash” crops, thus lifting the economy of four or five communities across the island. But the simpler truth is that the lack of diversity that monocultures implies leaves single crops open to many predators and disease and biodiversity–the hallmark of food sovereignty, indeed (ahem) of nature, makes food crops healthier. Something every peasant knows.
So–“discovery. . .” You’ll find that when non-experts seize on almost any idea, it’s a discovery for them!
“Trap-cropping is a form of interplanting, practiced by every small farmer in the world.”
I think it’s practiced by small farmers because that’s where the knowledge has survived and been retained. It’s also easier for a smaller farmer to ensure the practice occurs. If you’re planting 1,000 acres of corn you are likely hiring out some of that planting process. If you want to incorporate some form of interplanting you’ve now added in another layer of administration and management to get it done. When you’re overworked and overtired and your family hasn’t planted that way in 2+ generations it probably isn’t going to get done.
There was a time where farming in America was done much differently than it is done today and where the farm family was almost self-sufficient. When my grandfather was a kid his family’s dairy farm provided almost everything and they behaved in a way where they thought of themselves as stewards of the land so that they land could continue to provide for them. They didn’t just raise cows for milk to sell, they raised pigs and chickens to feed the family and provides some extra side income. They had a small orchard with apple and pair trees. They had over 50 acres of wooded land to provide lumber and firewood. They pastured their cows on land a mix of permanent pasture and fields that would periodically be plowed and planted.
In todays world you can find giant dairy farms in the extremely dry area of New Mexico where 90-100% of the cows food is trucked in and the cows never leave a concrete pad. Industrial agriculture is absolutely awful.
Yves, thank you for this article. Not sure if Lyman AB found a solution for the earwigs. Beer traps work.
Trying to revive family farmland in Greece. My biggest issue is water quality as the drought has changed the water table and salinity has entered the aquifer (alas our land is near the coast). Switching from citrus my father planted in early 80s to olive varieties that are less affected by salt. Will look into any salt tolerant trap plants that help phytophthora and various insect pests of olive (dacus – the olive fly and leaf hoppers that transmit the dreaded xyllela virus).
Please keep these articles coming! NC is truly a treasure!
My solution so far has been to stop planting marigolds to see if that will reduce the earwig population. I also made sure to clean up any small piles of dead leaves that accumulate in corners around the yard since they create the little damp, dark spots that make prime earwig habitat. I did try beer traps last year and did not get any earwigs or slugs in them, but I did notice fewer earwigs overall around the yard. Besides the earwigs, I had also been inadvertently breeding a few different beetle species which also like to eat similar plants. Work in progress – just glad that I don’t depend completely on my vegetable garden and there’s still a grocery store nearby!
Also, from the article above –
“Marigolds not only deter pests; they also attract bees and other pollinators that aid chili production.”
Since Yves remembered my comment in the intro (thank you!), I did want to point out that the earwigs only chew the marigold leaves, and very slowly. So they’re really only a problem if they get out of control – a few won’t do much damage. They leave the blossoms alone, so even if you lose some greenery, they’ll still bring in pollinators with the blossoms. Definitely give marigolds a try!
It’s been years since I was vegetable gardening so not a lot is top of mind for me anymore, but I’d suggest you find another trap crop and then rotate it with the marigolds every other year.
ddt:
Here is an article in English from a grower in the Kalamata region.
https://oliviadaolive.com/best-companion-plants-for-olive-trees/
Some of the companion plants that he recommends are surprising: borage (?).
Nasturtiums and thyme are tough and may serve your purposes.
Also, I recently read Agrumi by Giuseppe Barbera, which is a history of citrus trees and fruit in Italy, going back to the earliest citrons. Barbera is a retired professor of tree science at the Uni of Palermo, and he maintains that in some parts of Sicily and on Pantelleria, oranges were grown with almost no watering, using various techniques like gathering water vapors. The book is not likely available in English or Greek, but you may have access to someone who knows low-irrigation citrus-growing techniques.
Cover crop Rye is a great nematode trap crop. They crawl in early spring and then the crop is turned under. A single Rye plant has an almost unbelievable amount of root length for them to climb into.
I thought Marigolds were a repellent crop? And then only certain species…
Some other terms to look into related to this would be “companion planting”, and “integrated pest management”.
Companion planting is similar to pest management but less of a trap and more symbiotic.
Integrated pest management can incorporate non-biological controls but has concepts like using insects to control pest insects.
Another thing you might want to look into if you’re interested in this sort of thing is the concept of “the three sisters”. In North America this is typically Corn, Squash, and Beans. What’s interesting is that these three foods contain most of the nutrition needed for people to survive.
From Wikipedia: “In a technique known as companion planting, the maize and beans are often planted together in mounds formed by hilling soil around the base of the plants each year; squash is typically planted between the mounds. The cornstalk serves as a trellis for climbing beans, the beans fix nitrogen in their root nodules and stabilize the maize in high winds, and the wide leaves of the squash plant shade the ground, keeping the soil moist and helping prevent the establishment of weeds.”
In South America and Asia I believe there is a similar trio that is common to the diets, but I’m not sure about the history of companion planting them. Im basing this off the Blue Zones miniseries that talks about areas that people live longer on average and I just noticed the similarities in stable foods. (Spoiler: exercise was a massive factor)
We’d used companion planting 40yrs ago, due to unusual consensus of elder refugees trying to survive Reagan, by community gardens (foraging, fishing, dumpster diving & varmint hunting). Seemed to be pretty widely used (SE Asians, Jews from Ukraine, Lebanese & West Africans) Wonder, if robotic trimmers can outdo predators & microorganisms, before agribusiness GE monoculture, AGW, agri-business & fracking brine kills us all?
sluggoX works wonders on earwigs, and is OMRI certified. Earwigs were decimating my chinese cabbages, until I applied SluggoX.
Also, note that if you feed marigold flowers to your chickens, it ups their omega 3 content (and the yolks get yellower), and the chickens are happier.
Thanks ISL. Nice tip for the hens.
Isn’t sluggo – specifically one of the ingredients, Ethylenediaminetetraacetic acid – toxic?
I had understood EDTA to be a “chelator”. Here is a wikiped about it.
https://en.wikipedia.org/wiki/Ethylenediaminetetraacetic_acid
Yves,
thank you. As some folks above commented Marigold’s scent attracts pollenization and repels fleas, the roots emit substances with an insecticide effect on parasites.
I’d like to mention also as part of Day of the Dead activity we build altars which are effusively decorated with Cempasuchil (Marigold) because it is believed the scent leads the spirits of our departed to them.
i plant marigolds every year…and save the seed.
they repel all sorts of stuff, in addition to the antinematode effects.
as someone said above, rye is great for nematodes…if you till it up in early spring, or even earlier(chickens are tasked with this, right now, in all the big raised beds).
all my salad stuff…lettuce, radishes, etc…i grow in fall and through the winter, given where im at…a companion for this is mustard. i keep a big patch of mustard growing all winter, away from the salad garden…and harvest the leaves as wanted…and seeds in spring.
in early spring, the various inchworms prefer mustards to lettuce, spinach, etc…so they flock to the mustard patch(es)…which can be opened up to the chickens at such time…just ere i migrate them across the road for spring.
i really dont have many pest insects…cousin brought in red spidermites in 2020 with a storebought tomato plant…and they got into the little greenhouse every winter.
so i did the treatment that alternates between dr bronners in light water solution, and pyrethrin(the strongest thing i use)…that knocked them down. then i ordered 1000 lady bugs and lacewings, and turned them loose in the greenhouse.
problem solved…and boosted the ladybug population around here(several cold winters).
all my birds keep the worst of the bad bugs down.
and the million dragonflies(which is why i provide habitat).
i do get squash bugs every year, but only on the bush type zukes…which is why i like vining curcurbits…i harvested 6# french pumpkins from a pine tree in august,lol.
growing curcurbits vertically discourages squash bugs(which chickens, et al, apparently find unpalatable.).
and like someone else said…all this is only “new” to academic farmers and pmc types,lol.
ive known to plant carrots and basil and marigolds in with the tomatoes since i was, like, 5.
and i dont do neat rows that are easy for bad bugs to exploit…i plant thickly…and everything all mixed up chaotically.
beans on same trellis as toms or growing up the same fruit tree as the cukes…fixing nitrogen.
can be a challenge to harvest,lol…but it works for me.
note that this doesnt work for taters…if you have permanent tater beds like i do…so those beds are shot through with garlic and onions and shallots…and black eyed peas..and ill toss a bunch of marigold seeds in there for good measure.
in winter, those beds get rye grass or wheat, which gets mowed ere it heads.
i havent had a nematode or a tater beetle ever, out here.
those taters are so far for emergencies…but test digs reveal just a whole lot of taters underground.
soon, ill hafta start eating them.
(those are all from the little bags of fancy fingerling taters one finds at HEB…as well as the red taters. i just dump em out and cover them with leaves and hay from the chicken house in fall…and away they go next spring. left of adding more a few years ago. get a farmerstiffy every spring when they come up thicker and thicker)
and im rambling…but soil health is yer best prevention from pests…rich soil makes for strong and resilient plants.
I second the Dr. Bronner’s recommendation. I have an nice azalea that got chewed by little green sawfly larvae. After trying a few different things without much success, spraying with the soap and water (and squishing some by hand) has done the trick. I’ve mostly broken their annual cycle now and instead of getting the whole plant covered with worms every year, I now deal with just a few. Found it best to start spraying as soon as it leafs out in the spring rather than waiting for the little buggers to show up first.
I’ve had trouble finding cempasuchil marigold seeds sold online or mail order and I’ve never seen them in a store.
Michael I can’t vouch for these guys, might be seasonal cause the comment below was about 4 months ago, they’re in Chicago their instagram @semillaschicago
“Cempasúchil pre-orders are now available online! We are accepting orders in-store as well.
link in bio 🌿”
https://www.semillaschicago.com/
Thanks for the link. At one time Seeds of Change carried cempasuchil marigold seeds and I was able to get them to flower but I don’t think any seeds resulted. I might have planted too late or cempasuchil didn’t like the growing conditions. Searching for many possible names brings up a few results and there might be some on eBay. I think I saw people with fresh flowers at an NC state park once, so the marigolds must be around. There was definitely the Latin American vegetable papalo (Porophyllum ruderale), and some major seed companies sell seeds. I’ve heard of marigolds being used to repel pests, but I’m interested in their history and culture. I’ve tried growing French breakfast radishes for pest control.
What Chinese agriculture scientists have been doing is collecting wild and cultivated plant samples internationally and slowly working through genetic histories of the plants and seed or tubers to find how different traits emerged over thousands of years. This means studying how African wild millets would become Egyptian wheat, growing the millets and wheat to tie related genetic makeups to traits.
https://english.news.cn/20241116/2015a3678bd64ed1bc2b5c23b1cb2b5a/c.html
November 16, 2024
Chinese scientists find new method to sweeten tomatoes
BEIJING — Many people share a nostalgia for the rich, classic flavor of tomatoes from their childhood. This longing is largely due to modern breeding techniques that prioritize high yields, often at the expense of the genetic factors that contribute to a tomato’s taste.
However, a Chinese team has found a way to genetically release the tomato’s sugar brake without sacrificing yield. This exciting development means that sweeter and juicier tomatoes may soon be making a comeback in supermarkets.
The researchers from the Chinese Academy of Agricultural Sciences conducted taste tests on over 100 varieties of tomatoes and identified 33 flavor compounds that affect consumer preferences.
Then, they analyzed the content of these flavor compounds in more than 400 tomato samples from around the world and conducted genomic sequencing. This led to the discovery of 49 genes that influence flavor, including two that regulate sugar content.
By simply knocking out two genes, the glucose levels in the fruits saw an increase of up to 30 percent. This modification could also have a similar effect on the glucose and fructose levels of mass-produced tomatoes. As a result, suppliers can sell sweeter tomatoes without having to worry about a decrease in fruit weight or yield, according to the study * published in the journal Nature this week.
The result raises the possibility of “using the great genetic diversity existing in wild species, which has been partially lost in domesticated varieties, to improve modern varieties,” commented Christophe Rothan, a fruit biologist at the French National Institute of Agricultural Research, in a viewpoint article.
It is also an important step forward in “understanding how fruits produce and store sugar,” according to the article.
* https://www.nature.com/articles/s41586-024-08186-2 **
** https://www.nature.com/articles/d41586-024-03722-6
“The world is a sacred vessel, which must not be tampered with or grabbed after.
To tamper with it is to spoil it,and to grasp it is to lose it.”
Tao te Ching #29 (trans. by Wu)
There should be a word for re-learning the forgotten techniques and making them new and useful again.
That word could be “retrovation”, the opposite of “innovation”.
The Indian farmer featured in this article was doing some real retrovation there. His resurrection of an old blast-from-the-past technique is very retrovative.
I think its a good word. If anyone else likes it, feel free to use it.
Though, to be honest, they’re NOT forgotten techniques, many people still use them. My mother did, back when she gardened, and my husband still does. The other thing about marigolds that no one has mentioned, but is important to me, is that they’re a beautiful dye plant! So you can kill two birds with one stone, so to speak. (I would never kill a bird!) Good for companion gardening and good for the home dye pot. Works well on protein or cellulose fibers!
Perhaps in this context, “forgotten” means “forgotten by the mainstream”. And now that the mainstream is having problems with its mainstream methods, so many problems that it is being forced to look back to older methods, perhaps the word “retrovation” is still fitting.
Retrovate. Retrovation. Retrovative.
Give people a word to think of something with, and more people might be able to think of that something.
Here is a magazine that highlights past-used but presently abandoned methods to do stuff. Some of these methods could work again, better in the widest scope than the way we are doing things today. Re-adopting these older methods would be very . . . retrovative. Maybe I’ll write these people and offer them the use of that word. Maybe they will like it. Maybe not.
A friend’s father was an avid gardener. What he did was take a strip of corrugated cardboard about 2 inches wide and (I think) about 12 inches long and roll it into a squat cylinder (so 2″ by 2″ say). Secure it with some tape then tie it in an appropriate location. He attached them to the supports and hardier stems of the plants. Every day or so detach the cylinders and shake them over a convenient piece of concrete or the like and crush the little darlings one by one. Then return the earwig motel to its place.
It won’t get rid of them overnight so persistence is still necessary but it did work. And he did have a lovely garden.
It’s not just plant-based techniques that can be used to keep pests in check. Here is one old technique from Thailand that works out pretty well as well-
https://www.youtube.com/watch?v=A3N6BG9owwk (2:00 mins)
India has been a source of sustainable agriculture for centuries of organic farming practices. China and Japan also knew how to farm productively without petrochemical inputs or fallowing. Sir Robert Howard in the early 20th century worked in all these countries and learned from them the composting methods that he was able to modify to be accessible to Western farmers. He is known as the “Father of Organic Farming”. https://www.historyoforganic.com/_files/ugd/976354_a193c3662ced448995e5fba7472682cf.pdf?index=true