Woke up to your beetroot babies chopped off at the soil like a veggie crime scene?
Yep, that’s probably cutworms—sneaky, night-crawling plant assassins. They’re a nightmare for root veg growers, especially beets.
But don’t panic.
This guide gives you straight-up, proven ways to spot, stop, and send cutworms packing—so your beetroot patch can grow strong, drama-free, and delicious.
Common Signs of Cutworm Damage on Beetroots
Think your beets are under attack? Here’s how to tell if cutworms are crashing the party:
- Clean-cut stems: If your seedlings look like they got chopped at soil level, that’s classic cutworm work. It’s like they bring tiny garden scissors to the scene.
- Sudden wilt + collapse: One day your plants are thriving, the next they’re doing a full faceplant. No warning, just plop.
- Leaf munching: Look for random holes or chewed edges near the base—cutworms snack low, like ground-level grazers.
- Vanishing seedlings: Planted yesterday, gone today? They didn’t ghost you—cutworms probably dragged them underground for a midnight feast.
- Weird soil marks: Tiny holes or disturbed spots around your plants = cutworm hideouts. They dig in like lazy vampires, feeding at night and sleeping all day.
Spotting these signs early helps you take action before your whole beet squad gets wiped out.
Prevention Strategies: Your First Line of Defense
Before you break out the bug spray, try these low-effort, high-reward moves to keep cutworms from turning your beets into an all-you-can-eat buffet.
1. Plant at the right time
Cutworms love late spring—they show up hungry and hit hard.
So, don’t roll out the beetroot welcome mat too early.
Start your seeds indoors, let the little guys grow in peace, and then transplant them once cutworm season slows down.
Think of it as skipping the line at the worst restaurant in town.
2. Keep your garden clean
Cutworms thrive in messy beds—like bad roommates who never move out.
Do this:
- Rip out weeds and tall grass—those are cutworm drive-thrus.
- Clear dead leaves and old plant junk—they love hiding in there over winter.
- Till the soil a couple weeks before planting—this flips their hideouts upside down and exposes them to birds and sun (aka their two least favorite things).
- Skip green manure or cover crops in high-risk spots—it’s basically cutworm takeout.
3. Soil management techniques
The stuff you mix into your soil can make or break your beet game.
Skip the fresh green mulches—cutworms love that like kids love candy.
Instead:
- Use fully composted organic matter to beef up your soil
- Keep the planting zone clean and clear
- Avoid piling mulch right up against your beet stems—you’re just rolling out the red carpet
Physical Barriers: Proven Protection Methods
If cutworms are the garden ninjas sneaking in at night, then physical barriers are your plant’s security detail.
Think of them like tiny armor for your beet babies—cheap, easy, and surprisingly effective.
DIY cutworm collars
Wrap each seedling in a little collar to stop cutworms from getting to the stem buffet.
Use stuff you already have lying around.
Materials:
- Toilet paper rolls (the MVP of garden upcycling)
- Aluminum foil
- Plastic bottles (cut the top and bottom off)
- Yogurt cups with the bottom popped out
- Store-bought garden collars if you’re feeling fancy
How to install:
- Push the collar at least 1–2 inches into the soil
- Let it stick up a couple inches above ground
- Press it in snug—no gaps or cutworms will crawl right under like sneaky little gremlins
- Keep collars on for 3–4 weeks, or until the stems are thick enough to handle themselves (pencil-width = safe zone)
Alternative barrier methods
Planting a lot of beets? Wrapping every stem might get old fast.
Try these crowd-control methods:
- Diatomaceous earth – sprinkle it in a ring around your plants. It’s like crawling over glass for cutworms (but safe for plants and people).
- Coffee grounds – caffeine = cutworm kryptonite. Plus, it boosts your compost game.
- Crushed eggshells – the sharp edges freak them out. Bonus: calcium for your soil.
- Wood ash – sprinkle lightly; cutworms hate it, but your soil only wants a little. Don’t overdo it or you’ll mess with the pH.
Biological Control Solutions
If you’re not into chemical drama and want to fight cutworms the crunchy, nature-friendly way—biological control is your jam.
Think of it as calling in nature’s hit squad to keep your beets safe.
Beneficial nematodes
These little wormy heroes—Steinernema carpocapsae if you’re feeling scientific—are invisible good guys that hunt down cutworms in the soil like secret agents.
You spray them into the dirt, and they do the rest.
How to deploy them like a pro:
- Water your soil first—nematodes like it moist, not bone dry
- Apply them in the evening so they don’t get fried by the sun
- Make sure the soil’s between 60–85°F—basically their sweet spot
- Reapply every 2–3 weeks while cutworms are active
- Lightly water again after applying to help them move into their new underground home
It’s like setting up a microscopic defense squad that eats pests from the inside out (yes, literally—it’s kinda metal).
Encouraging Natural Predators
Cutworms don’t stand a chance when your garden’s crawling (and flying) with their natural enemies.
Make your space a hangout for the right kind of creepy-crawlies:
- Birds: Put up birdhouses, birdbaths, or feeders to attract bug-munching birds. Robins are cutworm assassins in disguise.
- Ground beetles: Leave some undisturbed soil spots—they nest there and love snacking on cutworm larvae.
- Spiders: Yes, they’re a little spooky, but they’re also MVPs when it comes to pest patrol. Skip the pesticides so they can thrive.
- Parasitic wasps: These tiny warriors lay their eggs in cutworms. Brutal but brilliant. Plant dill, fennel, or yarrow to keep them around.
Organic Treatment Options
Want to wipe out cutworms without nuking your whole garden?
Here are some solid organic options that keep things green and get results—no sketchy chemicals, no guilt, just solid pest-fighting action.
Bacillus thuringiensis (Bt) Applications
Meet Bacillus thuringiensis (aka Bt).
It’s a naturally occurring bacteria that messes up caterpillar guts—but leaves your plants, pets, and pollinators alone.
Thuricide BT is the go-to brand for organic gardeners, and yes—it works on cutworms.
How to use it like a boss:
- Spray in the late afternoon or evening when cutworms crawl out for dinner
- Hit the base of your plants and the soil line—that’s where they feed
- Reapply after rain or deep watering (Bt doesn’t stick around forever)
- Catch them while they’re still baby worms—early hits work best
It’s like giving your plants a protective coating of “nope” for hungry caterpillars.
Handpicking and monitoring
If your garden’s small, nothing beats getting in there and handling business.
Here’s the routine:
- Check your plants early in the morning or at night with a flashlight (cutworms are basically garden vampires)
- Look around the base of wilted or cut plants, or under nearby leaves and mulch
- Spot a cutworm? Pick it off and toss it far, far away—or squish it if you’re feeling ruthless
It’s a little gross, super satisfying, and free. Like live-action pest control therapy.
Integrated Pest Management Approach
Want to actually win the war on cutworms? Don’t rely on just one trick.
The best way to protect your beets is by combining smart moves into one master plan—like assembling your own garden Justice League.
Here’s how to layer your defense:
Combining multiple strategies
The most effective cutworm control combines several approaches:
- Prevention: Good timing, clean soil, and no plant junk lying around. Think of it as locking the doors before the party crashers show up.
- Physical barriers: Cutworm collars = your seedling’s personal armor.
- Biological control: Nematodes and helpful predators are your silent bodyguards.
- Organic treatments: If you spot damage, spray it down before they multiply.
- Monitoring: Check plants regularly and handpick the troublemakers like a stealthy garden ninja.
Seasonal management calendar
Here’s how to stay ahead, season by season:
Early Spring (March-April):
- Till your soil and clear out winter leftovers
- Apply nematodes to the soil (they’re like pre-installed security)
- Start beet seeds indoors to dodge early-season cutworms
Late Spring (May-June):
- Add collars when you transplant those baby beets
- Check daily for chewed stems or vanishing seedlings
- Spray Bt if you see signs of an attack
Summer (July-August):
- Keep an eye on plants, but the danger is lower
- Remove collars once stems are thick enough (pencil-size = safe zone)
- Start prepping your soil for fall beets with clean-up and prevention in mind
Troubleshooting Common Issues
Tried all the tricks and those little soil goblins are still slicing up your beets?
Don’t worry—it happens to the best of us.
Here’s how to level up your defense without losing your cool (or your crop).
When cutworms persist
- Dig those collars deeper. If they’re too shallow, cutworms sneak right under like it’s a tunnel escape scene. Bury collars at least 2 inches deep and 2 inches above ground.
- Go wider. Treat beyond just the plant. Cutworms don’t RSVP—they wander. Expand your coverage area to stop stragglers.
- Hunt the hideouts. Weedy patches nearby? That’s probably their Airbnb. Clean it up and check for cutworms chilling under debris.
- Hit the whole bed with nematodes. Don’t just spot-treat. Soak the whole zone and let the tiny assassins go to work underground.
Balancing organic and conventional methods
We all love a crunchy, organic garden vibe—but when it’s full-on beetroot apocalypse, sometimes you gotta consider Plan B.
- Start with the gentlest stuff. Bt, handpicking, collars—stick to those as long as you can.
- Hit early. The smaller the cutworm, the easier it is to take down. Don’t wait until they’re chewing like it’s a buffet.
- Go targeted, not scorched earth. Spot-spray instead of blasting the whole garden. You’ll avoid harming the good bugs who are on your side.
- Watch the side effects. Some treatments mess with beneficial insects, so always read the label and think twice before going full Terminator.
Long-Term Garden Health
Beating cutworms isn’t just about short-term wins—it’s about building a garden that naturally keeps them in check, season after season.
Here’s how to turn your beet patch into a fortress of balance and bug-fighting bliss.
Building cutworm-resistant garden ecosystems
Creating a balanced garden ecosystem reduces cutworm problems over time:
- Rotate your crops. Don’t plant beets (or any cutworm magnets) in the same spot every year. Keep those worms guessing.
- Companion planting = garden squad goals. Tuck in herbs like basil or flowers like marigolds next to your beets. The smell throws cutworms off—and looks cute too.
- Add habitat variety. Create cozy spots for beneficial bugs and birds. They’ll stick around and do pest control for free.
- Feed your soil. Healthy soil = strong plants = less cutworm damage. Compost, mulch, and keep the underground crew happy.
Sustainable Practices for Future Seasons
- Take notes like a garden detective. Track when cutworms show up, what they target, and what actually works.
- Build your own bug army. Grow a variety of plants that attract the good guys—wasps, beetles, birds, even spiders. The more diverse your space, the more balanced your bug life.
- Share your wins. If you find something that works, tell your garden club, your neighbor, your cousin with the container garden.
Wrap-Up: Beat Cutworms, Save Your Beets
Cutworms may be sneaky little soil ninjas, but with the right game plan, you’ve got this.
Start early, stay consistent, and mix it up—collars, nematodes, Bt, clean soil, and a few tough-love garden habits.
The secret sauce? Layer your defenses and don’t wait until they’ve already struck.
A little effort now means more beets later—and fewer midnight garden meltdowns.
Keep your garden balanced, your timing sharp, and your sleeves rolled up. With a smart strategy and some persistence, your beets will thrive—and cutworms won’t stand a chance.
