What's eating my common gladiolus?

Common gladiolus (Gladiolus communis) is most seriously damaged by gladiolus thrips — a tiny insect that attacks foliage and flowers in summer and then burrows into stored corms over winter. Aphids vector viruses. Caterpillars and cutworms chew through spikes. Treating corms before storage is as important as in-season spraying for keeping gladiolus clean year after year.

Cause silvery-white flecking and streaking on leaves and petals; heavy infestations turn foliage brown and prevent buds opening; corms develop rough, grey-brown corky patches in storage Spray with insecticidal soap or spinosad during the growing season before flowers open; store corms at 35–40°F (2–4°C) to kill overwintering thrips; soak corms in dilute bleach solution before boxing for winter

Cluster on flower spikes and leaf bases, transmitting cucumber mosaic virus and causing yellowed, mottled foliage and distorted flowers Strong water jet or insecticidal soap spray; introduce ladybirds; remove and destroy virus-infected plants; do not save corms from infected plants

Caterpillars chew holes in leaves and flower spikes; cutworms sever stems at ground level overnight, causing sudden plant collapse Hand-pick caterpillars; apply Bacillus thuringiensis (Bt) spray to foliage; use cardboard collars around stems to deter cutworm; cultivate soil around plants to expose and destroy pupae