What's eating my dutch iris?

Dutch Iris (Iris hollandica) is vulnerable to iris borer caterpillars, aphids on flower stems, and ink disease fungus destroying bulbs. Thrips scar petals. Slugs and snails chew emerging shoots in spring. In cut-flower production, botrytis grey mold is also a concern. Remove old foliage promptly each autumn.

Larvae notch leaf edges then bore down into bulbs; infested bulbs turn soft and foul-smelling Destroy old foliage in autumn; hand-pick larvae from leaves in spring; use nematode soil drench

Dense colonies on stems and buds cause sticky honeydew, sooty mold, and weakened flowers Spray with insecticidal soap or neem oil; encourage natural predators; remove heavily infested shoots

Silvery streaks and flecking on petals; flowers look damaged or fail to open cleanly Use sticky blue traps; apply spinosad spray during bud stage; remove spent flowers promptly

Fuzzy grey mold on petals and leaves; flowers collapse; spreads rapidly in cool humid weather Improve air circulation; remove infected tissue immediately; apply copper-based fungicide if necessary