How to control garden pests without using chemicals

A 7cm southern hawker dragonfly is eyeballing me or, more accurately, eyeing me with 30,000 of its lenses. As I wade further into the pond to pull out long green strands of blanket weed waving over the bale of barley straw, which is supposed to kill off the wretched stuff (just saying), the green, black and blue entomological biplane lunges at me.

I am not a wimp. I have stood up to Fleet Street editors, braved Royal Horticultural Society judges and dangled from the end of a rope out of a Royal Navy helicopter. But the southern hawker’s close attention is unnerving.