What's eating my dahlia 'thomas edison'?

Dahlia 'Thomas Edison' is vulnerable to the same dahlia pest set: slugs on new shoots, earwigs hiding and feeding in the dark-purple blooms, and aphids on soft growth. Spider mites can colonise stressed plants in dry summers. Slugs are overwhelmingly the biggest risk at planting time.

Large irregular holes in leaves and stems; emerging tuber shoots eaten to the ground. Ferric phosphate pellets around tubers at planting; nighttime hand-picking; beer traps; dry mulch.

Petals and leaves with ragged holes, most visible in the morning; insects shelter inside flower heads. Inverted pot traps stuffed with straw placed on canes near plants; check and empty traps daily.

Curled, sticky shoot tips with visible colonies; reduced vigour and bud distortion. Knock off with water; insecticidal soap; encourage ladybirds; avoid high-nitrogen feeds that drive lush growth.

Fine pale stippling on leaf undersides; silky webbing in hot, dry conditions; leaves bronze and drop. Improve humidity; spray undersides with water or neem oil; use predatory mites (Phytoseiulus persimilis) in greenhouses.