Treatments for Caterpillars on Poppies

Caterpillars

• Caterpillars are the immature form of adult butterflies and moths. Butterflies and moths lay eggs on the leaves of plants like poppies, and the eggs incubate there until ready to hatch. Once hatched, the larvae grow into caterpillars of different sizes depending on the type of butterfly or moth they will mature to be. The caterpillars feed on the leaves, stems and flowers of the poppies they infest in order to receive the nourishment they need to grow and survive. When they become old enough, the caterpillars create cocoons used to fully develop into their mature adult forms. Corn earworms are one of the most common varieties of caterpillars attacking poppies.

Damage

• Caterpillars damage poppy foliage by consuming entire leaves or chewing holes into leaves. Certain varieties of caterpillars eat only surface layers of leaves or use silken threads to attach themselves to leaves and create cocoons. Stems may suffer cankers, holes and severe damage to stems of young poppies. New buds on the plant may be consumed or bored into by caterpillars. Caterpillar damage leaves your poppy plant open to bacterial, fungal and viral disease infection.

Control

• Insecticides are effective in treating caterpillar infestations on poppies. Choose an insecticide formulated specifically for caterpillars that also is labeled safe for poppies or flower gardens. Carefully read the instructions on your insecticide's label and follow them exactly. Insecticides may be conventional or organic, depending on your preference. Bacillus thuringiensis is a natural soil-borne bacterium sold in garden supply stores. This bacterium is safe for humans and animals and will not damage your poppies, but it will deter caterpillars.

Prevention

• Preventing caterpillars in your poppies is the best means of control. Treat your poppies for caterpillar infestations regularly even if they do not appear to be infested. This stops infestations before they start. Introduce beneficial wasps to your poppy garden. Not only will they eat the caterpillar eggs and larvae, but they also will help pollinate your flowers. Finally, till up your flower bed each fall and spring to help kill out any caterpillar pupae that may have survived in the soil.