With each passing year I try to be more relaxed about “pests”. Squirrels make me cross but I have learned to deter them by planting things they don’t like – such as alliums and narcissi. Aphids are a promise for hoverflies, ladybirds and blue tit fledglings. Molluscs are tedious but they not physically capable of eating everything in the garden.

Vine weevils, on the other hand, are something I’d like to warn you about – mostly because, as a former container gardener, I know the devastation they can wreak. It’s all well and good being laissez-faire about a bit of casual munching when you have dozens of plants, but if you’ve only got a handful it’s rather more noticeable.

They are sneaky little blighters – elusive and nocturnal – so it’s easy to be ignorant of their presence until it’s too late, especially if you’re a beginner gardener. While the adults make Pac-Man-style chomps in foliage (they largely attack ornamental plants), the young grubs are the most destructive, eating root matter until you’re left with a deceptively healthy plant crown that comes away effortlessly from the soil like a kind of leafy hat – as has happened to me all too often. You can’t regrow the roots of a vine-weeviled plant. It’s toast.

Folding nematode application into your gardening calendar is one of those boring but good habits

While vine weevils do provide sustenance for other insects, birds and desirable garden visitors such as hedgehogs and frogs, their predilection for containers makes it less likely that you can rely on the Animals of Farthing Wood to help out. Throw in the fact that they can lurk in compost and come marching in through the soil of plants brought in from, for instance, a flower market, and they’re worth dealing with.

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So, what to do? I’m not suggesting you buy pesticides, but with the weather getting warmer and a strong chance of a drizzly day, now is the perfect time of year to apply nematodes. These are microscopic worms that work in a grislier way than the weevils themselves, entering the bodies of the grubs then feeding off them. It’s not pretty, but it is organic, won’t harm your children or pets and, crucially, will keep pest populations at bay.

Folding nematode application into your gardening calendar is one of those boring but good habits that ultimately pays off. You can also use them against slugs and ants.

Making sure the weather is the right kind of mild (between 5C and 20C generally, but check the packet) and overcast (to help the nematodes survive long enough to get to those grubs) is important, as is mixing up the brew to get them to the soil. I use a large enamel jug, a watering can with a coarse rose, a five-litre bucket and a big stick for stirring.