Garden Pests: The Tomato Cutworm

I have grown gardens in four different locations in Oregon, each over 50 miles from the others. Our home in Seaside is my fifth location.

I was pretty confident in my gardening prowess until one morning I came out to gaze upon my newly transplanted tomato starts and five of them had no leaves.

A brief Internet search concluded that my garden had been ravaged by early tomato cutworms. These malicious little beasties that come out at night to literally cut your tomato starts to the ground. If you go out at night you can catch them in the act, they look like pudgy caterpillars usually in pale green or shades of brown. There are also cutworms that target the plants after they have started bearing fruit, but we’ll cross that bridge when we get to it. Hopefully we won’t get to it.

The sadistic little worms left just one leaf on this plant.

Now, I’m not one to use pesticides haphazardly, but these creatures posed a threat I could not overlook. The year prior had yielded a sub-par tomato harvest and spending the winter buying store tomatoes instead of using homegrown, home canned goods, nearly killed me. However, it seemed there was a few alternatives I could try before I went to chemical warfare.

The first line of defense: tomato collars. This is basically just putting up some barrier around the tomato starts that the cutworms won’t crawl over. Different sources advise using cardboard, foil, tin cans, aluminum cans, or even plastic. I immediately set to work cutting out cardboard collars for my remaining plants, thanking the heavens I started more plants than I really wanted.

The most simple one I saw was cutting a section of cardboard in a square or circle. I cut squares approximately 5-6 inches long on each side. Then cutting a straight line halfway into the shape, you cut a small circle, just bigger than the plant’s stem. This can be opened and slid around each start.

A great use for junk mail to boot.

Another method was using cardboard tubes from paper towels or toilet paper. Cut sections of the tube just short enough to be below the lowest set of leaves. Then cut straight down the tube. This can be opened and placed around the stem of each plant, pushing the tube into the dirt to secure it closed.

I also cut the ends off a pop can and put this around one plant that had already been chewed on a bit. It was just a test really, I thought this plant wouldn’t come back from the damage it had undergone (spoiler: it came back with two tops but is filling out nicely and has blossoms!).

The plant was mutilated prior to placing the collar, however no more damage has occurred since then.

It’s been about a month since I placed the collars, and so far they have been working. I try to check them every day to make sure they stay intact. One collar came off a plant recently that’s about 8-10 inches tall and it has not been attacked, perhaps it’s past the most fragile stage?

My favorite of the few types I tried are the flat cardboard pieces, they are the most secure and easiest to make. They do make it harder to water the plants, but they keep the weeds down and keep the ground moist longer than if the plants had nothing. If I were to use the cardboard tubes again I would want to figure out a way to keep them closed better as when they get wet they tend to want to unfurl, leaving the precious plants unguarded. The pop can is definitely the most sturdy, but the edges are rather sharp and could hurt the plant if it rubs up against them; it was also took the longest to make (and made me cringe while I used scissors to cut the can).

Because the collars worked so well, I did not have to proceed to other methods. Some alternatives that I didn’t try but have heard work well include sprinkling corn meal around the plants, as apparently this is toxic to the worms and they will eat it before getting to your plants. Placing Popsicle sticks on either side of the stems, which is the same idea as the collars but they also can support the plants a bit more. I have also seen beneficial predatory nematodes (microscopic worms) for sale that will do the dirty work for you, attacking soft bodied garden pests and protecting your plants.

I have found a worm or two, and it is immensely satisfying to toss them into the chickens’ run and see the girls run around with their tasty little treasures.

Author: Kaya

Kaya Diem has been farming on some scale since 2007, from rabbits to radishes and sheep to squash, she hopes to someday be as self-sufficient as possible. Kaya graduated from Oregon State University in 2014 with an Animal Sciences degree. She lives in Seaside, OR with her husband, dog, and various farm critters on about 5 acres.

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