If you have some new seedling coming up, and some seem to be clipped off right at the soil level, it may be cutworms. These pests feed on blossoms and leaves of many ornamental plants and attack most edible garden crops, clipping off seedling stems near or just below the soil level. A few species chew holes into leaves or bore into heads of lettuce or cole crops. Holes may be chewed in young fruit or vegetables, and fruiting stems wilt and fall. New shoots may be eaten partway through.
Cutworms are dull brown caterpillars, 1 to 2 inches long when fully grown that curl into a C-shape when disturbed. Their smooth skin and markings blend well with the soil making them difficult to see. Normally they are found on or just below the soil surface or on lower parts of plants and are commonly active at night.
These critters are pests mainly in the spring. To help manage these pests:
- Destroy crop residues; keep garden weed-free in winter.
- Hand-pick at night with a flashlight.
- Clip and dispose of infested foliage and blossoms.
- Protect seedlings with cardboard collars, screens, or protective cloth.
- Plant more than needed to allow for some losses by these pests.