Scientists call it allelopathy.
Actually, it is just one form of allelopathy.
We call it companion planting and my all-time favourite in the garden is the bog-standard practice of planting tomatoes next to marigolds, which are said to keep away a soil nematode that can damage the crop.
I’ve never had a comparable non-paired-up plot, but I have had enough tomatoes each summer to host my own La Tomatina Festival without the pricey ticket to Spain.
The combinations of companion planting in the vegetable garden are endless, and yet it is just the surface being scratched when you consider the complexity of ecosystems where a food web can look a lot like a Year 5’s macramé project.
Some farmers are taking the more complex idea to a smarter level, adopting an approach of planting entire ecosystems on their allelopathic quest.
Dairy farmer Lauren Finger showed a conference last year a photo of her pasture which would in the past have had a farmer roll eyes at the work needed to get the landscape looking like the perfect monoculture patchwork quilt.
But you’ll find that the Finger family’s Friesians foraging unfamiliar fields are doing fine.
Lauren says soil health was key to the plant selection, with the oddest inclusion being dock weeds (yes, that’s what I thought) whose long and hard carrot-like tuber breaks up soil to allow better aeration and water penetration.
If you’ve ever tried to pull one out, you’d believe it.
Callum Lawson’s sowing of a variety of forage plants outside of Avenel has already been well-reported here, particularly his addition of nutrient for soil-borne organisms.
The thought of molasses being poured into the ground still rattles my sweet-tooth, but the well-fed microbes result in a more productive paddock.
Over the hill from Callum’s venture is Matt Fowles, who produces wine with an awareness of how eco-diversity can help growing vines.
Look underneath his vines and you see what most would describe as a bed of weeds when in fact it is a lush ecosystem of grasses and legumes which do more good for the vines than you’d suspect.
This is where the macramé comes in.
The undergrowth shades and cools the soil, acts as a mulch when it dies back at summer’s end, hosts an entire menagerie of insects which can support pollination (vines are primarily wind-pollinated but every bit helps), provides nitrogen and could well draw more pest-eating bats at the cost of a bit of collateral damage to other species.
How much of that is speculated?
All of it, but each thread woven into the macramé is scientifically documented in some way or another, and seasoned experiments show in many cases that production increases when biodiversity is nurtured.
This makes it plausible — all of it.
Insects and biodiversity help much more than we will ever comprehensively know; and if you think about it, the biodiversity was doing just fine thanks very much before we came along.
Sustaining natural ecosystems around the farm is full of much potential waiting to be found.
In the UK, folk are encouraged to leave a small triangle of their lawn entirely unmowed to provide a habitat for insects.
(I assumed my brother in Colchester had simply run out of two stroke — didn’t that go down well.)
When the patch grew back the next year, I maintained my protest at the untidiness.
“And what about that stinging nettle?“ I pointed and, right on cue, I accidentally touched the bloody thing.
Karma bit me twice: the throbbing finger justified my rage at the lack of monoculture.
My brother then gently reached into the sward and plucked a leaf from a dock weed.
Its sticky sap was — unknown to me — nature’s own antidote for stinging nettles.
The pain vanished.
Biodiversity in action.
Andy Wilson writes for Country News. He is a pre-peer review science editor in a range of fields and has a PhD in ecology from the University of Queensland.