Cutworm

Ever stepped out into the patch in the morning to find your seedlings cleanly cut off at the base, as if by a pair of sharp scissors, with the freshly snipped tops lying nearby? “It couldn’t be the neighbours, could it? We’ve been getting on so well lately, even after that pruning debacle!”

There’s a more likely cause: cutworm. Cutworms are the caterpillars or larvae of certain types of moths. They prefer to feed on very soft plants – such as seedlings – and yes, they just chew through the stems at ground level and then keep on moving. How annoying!

You don’t normally see them because they prefer to do their damage at night, while you’re sleeping. During the day, they crawl up and hide under mulch, leaves or chunks of soil where they can sleep safely and comfortably, protected from hungry birds. It’s unlikely that your tiny seedlings will recover, so if you have an unwelcome visit from a couple of cutworms, you will need to replant and then protect your new seedlings from further attack.

Start by clearing the mulch from the bed where the seedlings are to be replanted. Taking the mulch away removes any easy hiding places and may even dislodge any caterpillars that are currently in residence. You can return the mulch when the plants are reasonably established, with thicker, less palatable stems.

Next, grab some plastic drink cups or small unwanted plastic plant pots and cut off the bases. Once you have planted your seedlings, push a plastic cylinder into the soil around each seedling. Make sure that there is at least 6cm of the cylinder left above the ground. This creates an impenetrable wall for the caterpillars (they’re not known for their courageous climbing abilities), allowing your seedlings to settle in and grow unharmed.

Feed and water the seedlings as usual, and once they have gained some size and developed a firm stem, you can remove their protective covers with confidence.

Header image by iStock