Scottish bloody bluebells

This, in case anyone needs it made clear, is a Scottish Bluebell - not the English variety you understand but a hardy, resilient, bloody-minded Scottish type.

It's also a weed of the most persistent kind and despite repeated annual ministrations of the most potent poisons I can buy over the counter of my local garden centre, I still end up having to get down on my hands and knees and pull the damn things up from all over my garden. I tell you, as a species, it's absolutely bomb-proof.

Short of concreting the buggers over, if anyone has a fail-safe bluebell removal tip, I'd appreciate it...