Q What are these spores on my antirrhinum plants?
GRAHAM COE, BY EMAIL
A Yellow spots on the upper leaf surface and dark brown spores beneath are signs of antirrhinum rust. This is a common problem with snapdragons, especially in rural areas where the air is clean as this allows fungal diseases to become established. Fungicides such as FungusClear Ultra (£6.49 for 1L spray) and Bayer Fungus Fighter (£7.35 for 1L spray) offer some control of the disease if applied early in the season. Dig up and dispose of this year’s plants in your green waste bin (not your compost heap). Next year, try a ‘rust-resistant’ seed mix and trim off affected foliage if any sign of rust appears.