I was admiring how well the onions were swelling the other day, suddenly I noticed some of the leaves had been chewed in a neat circular way. Something had completely sliced open the tips of the leaves (bulbs are fine), so I did a bit of investigating to see what it could be. It didn’t take long to find the culprits way down inside the hollow leaves, complete with lots of green poop. Nice.
After a bit of research it appears the podgy caterpillars I found inside my onion leaves are cutworms. Cutworms are the larvae of several species of night flying moths, they’re not actually worms at all. Apparently, they’re a common visitor to the vegetable garden but I’ve never noticed them before, I mean, they’re not exactly easy to miss.
They hide in soil or under leaf litter, feeding on crops and other plants at night (more common early in the year), often cutting young plants or seedlings straight down to ground level. I guess that’s how they get their rather cruel name. When alarmed they curl into a C-shape, my personal observation is they have very sticky feet, making them difficult to pick off plants. They’re large and meaty so I didn’t fancy squishing them (I’m useless at killing things anyway), they’d make a heck of a mess. I simply moved on the ones I found and did a bit of hoeing to see if I could spot any lurking in the soil.
Gardening organically and living where I do I’m always going to have the odd ‘pest’ problem here and there, that’s how it goes. I don’t use nasty chemical sprays, my preferred method of natural control will be to keep a close eye for more, picking them off if I see them, digging the onion bed over after harvesting to expose any I may have missed. Cutworms have many natural predators including wild birds, our chickens will scratch in the onion bed later on in the year too.
Cutworms, your days are numbered.


















Southbourne Gardens
/ August 13, 2012I had some kale plants that fell victim to cutworms earlier in the year. I never did find the culprits. Have just tried to keep the soil well turned over to avoid.
matthaslam
/ August 13, 2012Interesting post. we had a huge problem about a month ago when over a two week period, all the tops of the onions were literally eaten off to the ground. Given the wet weather we assumed it was snails or slugs but weren’t convinced as the slimy guys don’t normally go for onions if there are alternatives! This could be it. : )
Karen
/ August 13, 2012Sounds like it could be cutworm. I went to my allotment today, the onion bed needed weeding badly. Sure enough, cutworm there too!
Caro (urbanvegpatch)
/ August 14, 2012This is not something I’ve encountered in the veg garden, Karen, so I’m glad to know about it. I also garden organically and feel that even caterpillars have their place in the system. I dug up some white pearl like objects a couple of weeks ago – they were slug eggs so needless to say they were bumped off immediately!
Flighty
/ August 15, 2012Thankfully cutworms are something that I’ve not yet encountered, but will keep an eye out from now on. My onions are okay although some had leaves eaten by slugs and snails! xx
Janet/Plantaliscious
/ August 16, 2012A new pest to look out for – not sure whether to curse you or thank you!!