The power to poison

Take care when buying farmyard manure, says Toby, as it may contain herbicides that can damage your plants...

- TOBY BUCKLAND

WHEN my friend Jim asked me to solve the mystery of a sickness plaguing his tomatoes, I thought it would be an open-and-shut case. Tomatoes often fall victim to the ‘usual suspects’ of leaf-blotching blight or are attacked by a virus that marks the foliage with mosaic-shaped ‘tattoos’. But what I witnessed when I stepped into Jim’s polytunnel was more puzzling.

The plants had been growing well, evidenced by healthy lower leaves and ripening fruit. But out of the blue, something had corrupted the newer growth, making the leaves weirdly thin and as rounded as ‘waxicles’ dripping from a melting candle.

I didn’t have a clue, but keen not to share this fact with Jim, I took a walk around the garden. And that was when I saw the roses. The briars had copy-cat spindly growth and a melted look – and a very worrying line of enquiry crossed my mind. Had Jim fed the toms and roses with the same manure? And could the dung be contaminated?