None of us likes to make enemies. My own feudaversiveness has me noshing mediocre restaurant fare with a smile on my face as the waitress hovers and remaining firm friends with motley ex-boyfriends, but it’s a different story when it comes to gardening.

Down on the allotment, I’ve acquired a vegetal nemesis. It’s prickly and pimpled in appearance, opportunistic and vindictive by nature, and quite impossible to be rid of. Its name? Helminthotheca echioides, though you might know it as bristly oxtongue.

By inclination I am a let-it-be gardener. Any plan has by midsummer given way to a wilful green tangle – uchiki kuri squash piggybacking on the runner bean poles, sweet peas entwined round sunflower stalks, and late beetroot squeezed into anything resembling a gap. Companion planting always carries a ring of Jane Austen; this is more happy hour at Jilly Cooper’s polo club.

Unsurprisingly, I started out as one of those who believe that a weed is merely a wild flower in the wrong place. They are of course vital to biodiversity and plenty have handy homeopathic uses. They have a nostalgic appeal, too, rooted in daisy chains and dandelion clocks, patches of clover in which to hunt for good luck. Weeds aren’t without their charms, either, be it the misleading delicacy of convolvulus trumpets or the enviable vase-life of ox-eye daisies.

I’ve learnt, though, that some weeds really are just weeds. Bristly oxtongue falls firmly into that category. A centuries-ago Mediterranean import, they’re easy enough to pull up in spring, before their roots have become baked into the earth, but even then, they’re like grey hairs: yank out one and three more pop up in its place.

Bristly oxtongue belongs to the daisy family and its flowers resemble dandelions, whose efficient parachuted seed delivery system it also shares. Its thick stem can reach almost a metre high and its branches are covered with distinctive pock-marked leaves, a prickle bursting from each scabby spot.

Attempts at finding redeeming features have failed – it’s apparently handy for expelling intestinal worms. Some weeds have evocative local names: its pseudonym is Milton Keynes Weed. Discovering it’s in decline in Northern Ireland and is being monitored by botanists, I did feel a fleeting pang of remorse. Very fleeting. Because ultimately, if you sow a seed you need to take responsibility for the seedling, and smothering, light-depriving, water-guzzling weeds will undermine all your best efforts.

Scheming to defeat them, gardeners learn more about the ways of weeds than we do many of the plants we cultivate. Perhaps because of the repetitive nature of uprooting them, these vagabonds can mess with the mind. Sun-addled, hoe in hand, it’s hard not to begin ascribing human traits to these varmints.

My own bête noire is sneaky and sly: I’ve found its stalk cosying up to foxgloves and other plants that it might fleetingly resemble, nestled root-to-root with anything bushy enough to provide cover for it. As for its vengefulness, those bristles may seem mild enough when the leaf is fresh, but on a piece that gets stuck to a gardening glove, say, where it’s left to dry out, they grow vicious enough to lodge splinter-like beneath the skin.

While few in the green-fingered community will indulge the view that weeds are merely a social construct, they do rely on us in other ways, thriving on human endeavour. Some — that convolvulus, for instance — will sprout new plants from every bit of broken root that the hapless gardener has failed to pull out. Others have responded to a liberal dousing of chemical herbicides by becoming tougher still and gaining resistance.

They’re at once a threat to civilisation and an emblem of hope. They’ve been a problem ever since Adam and Eve’s antics saw Eden overtaken by thorns and thistles, and however poorly we treat our planet — whatever the fate of our own species — any green shoot peeping up from the cracked tarmac will likely be a weed, perhaps even a bristly oxtongue.

As for my own campaign, I’ve discovered that the best way to battle these garden guerrillas is with their own kind.

Rather than swathing bare soil in plastic come autumn, I’ve taken to sowing it with green manure. If you can get the seeds in six weeks or so ahead of the first frost, crimson clover works wonders to improve the friability of clay soil and, left to flower in late spring, produces a patch of exotic, fluffy flowers buzzing with bees.

Rye grass will overwinter, too, producing rippling expanses with coppery lowlights, and for tall crops that need space — corn, for instance — low-growing trefoil will supress rival weeds by covering the ground.