What to Do if a Pansy Gets Worms?

Pansyworms

• Pansyworms feed by chewing holes in the leaves of pansies, violets and Johnny-jump-ups, as well as landscape plants, such as sedum, alyssum, moss rose and others. Pansyworm is a caterpillar measuring slightly more than an inch long, with a spiny, reddish-orange body with black or brown speckles or stripes. Eventually, pansyworm turns into a butterfly called a fritillary.

Black Cutworms

• Black cutworms, which turn into moths, are shiny, fat, dark-gray or black caterpillars with a pale, lengthwise stripe. The black cutworm, which measures about an inch long, is sometimes difficult to spot, as the worm hides in the soil during the day, emerging to feed on the foliage during the night or when the weather is cloudy. Young black cutworms chew the foliage. Mature cutworms through the base of the stem, and then dine on the felled plant all night.

Variegated Cutworms

• The variegated cutworm, destined eventually to become a moth, feeds on every part of the plant including the roots, stems and leaves. A fairly large caterpillar measuring nearly 2 inches, the variegated cutworm is green and black in its early stages, turning pale, mottled, greenish-brown at maturity. Variegated cutworms are usually easy to spot on the foliage, as the cutworm usually doesn't burrow into the soil.

Physical Controls

• Many cutworms and caterpillars are removed by picking the pests off the plant. Check your pansies daily. Carry a bucket of soapy water and drop the caterpillar or cutworm in the water, which kills them. Keep the soil around your pansies clean. Dispose of dead leaves, which provide a hiding place for caterpillars.

Control Measures

• Bacterial controls, such as Bacillus thuringiensis, are effective control measures for most cutworms and caterpillars, especially when the pests are small. The bacteria attack the pests' cells and digestive systems, killing them within hours. The bacteria doesn't harm people, pets or helpful insects, such as parasitic wasps or ladybugs. Insecticides should be used only when other means of control fail, as pesticides aren't selective and kill the helpful insects as well as the unwanted pests.