dandelion seeds on the wind

Obvious as the day is long—weeds and farming do not mix

Weeds and farming are bad, right? Well, that depends on the context and the truth may not be that obvious.

Ask most farmers and they will tell you that weeds and farming should not be in the same sentence but the blighters are inevitable, the bane of their existence.

Obvious as the day’s long”, my gran used to say, and your gran too, I guess. 

I remember she’d be on at anyone not able to see what was happening in the world around them, the nose in front of your face. Did you not know that Aunt Dot was on the sauce or that your sister’s friend Jill was two-timing her boyfriend with that clown Jerry from number 16?               

My experience is that many obvious things are mysteriously invisible. At least, that is the only logical explanation for why nobody seems to see them.

Here is a great example where weeds are good for farm productivity. The claim is that growing food is more profitable by letting the ecosystem do its thing and reducing the effort in fertiliser, chemical and labour costs that are usually spent to improve yields and curb weeds and pests.

A similar approach is taken in regenerative agriculture, syntropic farming and natural sequence farming, ideas that are on the fringes and taken up by true agricultural pioneers

Obvious when you think about it because plants, no matter what we choose to call them, are an excellent way to maintain nutrients and soil health.

Let’s back up a little though.

Farming for food and profit

Modern farms grow food and fibre for profit, fair enough. This means a product leaves the farm and ends up in a market as a salable commodity. Typically, this exchange results in money returning to the farmer.

At a base level, farming is the export of carbon and nutrients from the land to the sewer via the alimentary canal of humans or their livestock, a well-practised process that has been going on for over 10,000 years fuelled by ever-growing demand and lubricated by financial exchanges.

Obvious as the day is long.

What should also be obvious is that this is a one-way resource exchange—nutrients leave the farm. 

Most farmers know this only too well. They make sure to recycle as much of the non-salable parts of crops as possible, either into the soil or into livestock. They also convert some of the money they receive for their products into fertiliser to replace the exported nutrients. 

They spread inorganic nitrogen, phosphorus, potassium, trace elements, lime and the like to maintain soil fertility for as long as possible. Some do this organically through mulch, manure and cover crops. Others do both. 

All farmers know that if they don’t replenish the soil, crop yield declines steadily or even precipitously. This yield loss over time was why shifting agriculture was invented and then, through the boon of the agricultural revolution, why fertilisers became so prevalent.

A farmer who ignores the reality of nutrient export for too long or has no means to rectify the net loss and he goes out of business or, in the case of subsistence farmers, loses their livelihoods.

Just to note that around 2 billion people or roughly a quarter of the global population, in 500 million households living in developing nations’ rural areas survive as “smallholder” farmers, working less than 2 hectares (5 acres) of land.

Soil nutrients are critical to a lot of people.

Obvious as the day’s long.

Andronac chair overgrown at the edge of a field of weeds and farming

Photo by Adam Tagarro on Unsplash

Intensive agriculture, weeds and farming

In parts of Europe, North America and increasingly in Asia, the process of nutrient replenishment is finely tuned. 

Exact amounts of nutrients are added via inorganic or organic fertilisers and careful crop selection and rotation to replace the nutrients that have left so that a balance is created.

The nutrients are not lost because we know where they are; most of them end up in the produce that humans consume and then into the sewage system.  There are ways to safely recover some of these nutrients, and we will need to explore and implement many of them soon. The point here though, is that nutrients are lost from the farm.

This brings us back to the weeds and agriculture.

Using or accepting weeds in food production systems is an ecological way to achieve a similar result. Weeds help to replace the nutrients that the crops and livestock need mainly because they encourage retention and buildup of carbon in the soil. 

Carbon provides a buffer for nutrients. It can make artificial additions more effective and efficient as well as let biology do its thing to break down organic matter in the soil water system to make nutrients more available to plants.

Plants in the ecosystem are the way to speed up the creation of soil, that is the weathering of the inert parent material (rocks and sediment) to create an organic, biologically rich substrate where nutrients are readily available and exchanged.

Weeds, crops, cover crops, pasture, it really doesn’t matter what the vegetation is called but to maintain the nutrient exchange efficiency of soil for the commodities that humans want, there must be plants growing in it.

Weeds and farming need not always be negative.

Obvious as the day’s long.

daisy in a paddock

Photo by Rachilli on Unsplash

What was obvious to Grandma 

Grandma was more of a people person. She would be all over the latest gossip and knew exactly who to complain about next, it was uncanny. 

But she also had green fingers and would have followed the logic in this post, having applied it to her veggie patch for years. She pulled weeds from around the seedlings but had no problem with weeds growing over the soil once the harvest was in. She would have latched on to the logic of weeds and farming as fast as she would dob in your sister’s friend Jill.

When the soil is depleted, farms need weeds.
Obvious as the day’s long”, she would have said.

Asian grandma sitting on a log
Photo by Pisit Heng on Unsplash

What sustainably FED suggests…

There is a need to rethink much of what the convention says about how we manage land. At present, we default to clearing far too often—the innate response that gave us shifting agriculture—when we have smarter and more effective options to both restore productivity and slow down the depletion of both nutrients and carbon.

Weeds and farming are one of the conventions.

Farmers have to start thinking about carbon first and commodity second. When they do this, they will look to soil health with the same concern they show for the health of their crops or livestock. 

In some cases, what we call weeds are a legitimate way to keep soils healthy.

That you can achieve soil carbon benefits through weeds, plants that, by definition, are in the wrong place at the wrong time, comes with additional challenges. 

For example, weeds are considered untidy, and so if you leave them in the ground, you are not a ‘good’ farmer. Also, some weeds are indeed in the wrong place and should be removed or controlled immediately, especially those that are unpalatable or poisonous to livestock or likely to overrun all other plants. Such noxious weeds and farming stick with the convention. 

Sustainably FED suggests that everyone looks long to understand better the processes—ecological, economic and social—that maintain farm production and, ultimately, sustainable food.

A rethink of weeds and farming is a neat example of what this will take.

Obvious as the day’s long.

Hero image by Saad Chaudhry on Unsplash


Mark is an ecology nerd who was cursed with an entrepreneurial gene and a big picture view making him a rare beast, uncomfortable in the ivory towers and the disconnected silos of the public service. Despite this he has made it through a 40+ year career as a scientist and for some unknown reason still likes to read scientific papers.

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