Petunias (Petunia x hyrbrida) are low growing plants often grown as ground covers and in containers. The plants bloom from spring to winter with funnel-shaped or ruffled flowers in shades of yellow, red, blue, purple and white. Petunias are susceptible to worm infestation, among other disorders.
Tobacco budworm (Helicoverpa virescens) is a common pest of petunia. The pests overwinter in the soil during winter and are considered a serious problem in petunias. The tobacco budworm turns into a moth with a 1 1/2-inch wingspan.
Tobacco budworms feed on petunia buds and petals, damaging the flowers in the early developmental stage. Infested buds do not bloom. The flowers that do bloom have chewed and ragged looking petals. The worms continue to damage plants all through the growing season. Damage is most apparent during late summer.
Regularly inspect plants for effective early management. Tobacco budworms hide in the plant base during the day. Handpick the worms in case of light infestation. Bacillus thuringiensis is a biological control option. Synthetic pyrethrins can also be used for tobacco budworms