Keep the Ants From Marching In: Natural Peppermint and Diatomaceous Earth Fixes
Are ants infiltrating your home? Try these surefire natural pest deterrents!
Quick Reference
- Two remedies: a peppermint essential-oil spray and food-grade diatomaceous earth.
- Peppermint spray ratio: 4 oz water, 2 tablespoons vodka, 15 drops peppermint oil, 5 drops cinnamon oil.
- Fire-ant mound: dust the top thoroughly with food-grade diatomaceous earth, stir with a stick, dust again; expect 2-3 applications.
- Kid and pet safety: food-grade DE is used in grain storage; still, avoid inhaling the powder and reapply after rain.
- When to bring in a pro: more than 3 mounds within 20 feet of the house, or ants inside walls; call a licensed pest-control operator.
- Fire-ant range: USDA imported fire ant quarantine covers 13 southern US states, from Texas through the Carolinas up into southern Virginia.
Venturing outside for a leisurely picnic or a brief repose on the patio? Nothing turns barefoot grass time into a shrieking scramble faster than a mound of fire ants. Two natural remedies keep the yard, the patio, and the picnic blanket free of biting ants without pouring chemical bait onto the same ground your kids and dogs play on.
Fire ants recently set up camp just off our patio, beside the walkway, building more than one mound. Being so close to the house, we wanted to keep the area free of biting ants and toxic chemicals. Here is our nontoxic way to clear ants from the yard and patio, drawn from years of Almanac reader notes and cross-checked against USDA and Cornell extension guidance. If you have young children, you do not want their playtime ruined by painful fire ant stings. If you discover a fire ant colony in your yard, the two remedies below are safe, effective, and cheap.
Peppermint Ant Spray: How and Why It Works
Ants navigate by pheromone trails they lay down with their abdomens. Strong scents mask those trails and send the scouts home confused. Peppermint is at the top of the “ants hate this” list because the menthol overpowers the tiny chemical signals the workers rely on. A 2010 Journal of Pest Science trial found peppermint essential oil in a 1 to 3 percent water solution reduced ant activity by 70 percent within 24 hours.
The refreshing scent of peppermint is offensive to ants but pleasant to people. This fragrant, natural spray is safe to use indoors or out, whether you spot ants on your kitchen counter or your porch. Carry a spray bottle on your next outing and mist the picnic table or the ground around your blanket before dining, to discourage ants from invading lunch.
Ant Spray Recipe:
- 4 oz water
- 2 tablespoons vodka (acts as a co-solvent so the oils stay suspended)
- 15 drops peppermint essential oil
- 5 drops cinnamon essential oil
- Mix in a spray bottle, shake before every use, and spray as needed.
This fragrant spray doubles as a room freshener and ant deterrent. Store the bottle out of direct sun and remake a fresh batch every 2 weeks; the citrus and mint notes fade.
Diatomaceous Earth: What It Is and How to Use It
Wondering what diatomaceous earth is and how it works? It is powdered shell flour, a natural product composed of ground diatoms (a type of ancient marine algae). The tiny white crystals are not harmful to human touch or consumption, but they will effectively eliminate soft-bodied ants and other pests like fleas. The mechanism is mechanical, not chemical: microscopic sharp edges scrape the waxy layer off the insect exoskeleton, and the ant dies of dehydration within 24 to 48 hours. The National Pesticide Information Center at Oregon State University confirms this is why DE works on any hard-shelled insect it touches.
To use on a fire ant mound, cover the top of the mound thoroughly with the powder (be sure to purchase “food grade”). Stir the mound with a stick and apply more diatomaceous earth. Only the ants that come in contact with the powder will be destroyed, as it does not penetrate deep into the colony like chemical poisons. You may need more than one application to eliminate the entire colony. If ants are making a trail across your porch, deck, or patio, lightly dust them with a coat of diatomaceous earth.
Diatomaceous earth is also safe to use for insect control in the garden or greenhouse. Sprinkle it onto plants to deter harmful insects. Apply a ring of DE around the perimeter of a raised garden bed to keep ants at bay. You will need to reapply after rain, because water clumps the powder and eliminates the sharp-edge effect.
Be careful not to breathe in the powder. Wear a simple dust mask when dusting large areas. Keep pets out of the treatment zone until you have watered the powder into the soil surface.
Where Fire Ants Actually Live in North America
Fire-ant biting is regional. The USDA Animal and Plant Health Inspection Service maintains an imported fire ant quarantine covering 13 states from Texas east through the Carolinas and up into southern Virginia. Northerners more often battle sugar ants, pavement ants, or carpenter ants: painful bites are less of a worry, but the peppermint spray and DE ring still deter foraging trails.
- South (Zones 8-10): imported red fire ants, big mounds, painful stings; DE and boiling water combined are the reader-tested trick.
- Mid-Atlantic and Midwest (Zones 5-7): pavement ants and small carpenter ants; the peppermint spray on trails and window sills works within a day.
- Pacific Northwest and Canada: odorous house ants and carpenter ants; find and dust the nest with DE where the trail disappears under siding.
- Southwest (Zones 8-9): harvester ants sting hard; use DE, and never step on a mound.
Kid and Pet Safety Notes
Food-grade diatomaceous earth is used in stored-grain protection and is considered generally recognized as safe for consumption in trace amounts by the FDA. That said, the powder is dusty. The EPA guidance on natural pest products recommends the same rules for essential-oil sprays and DE:
- Apply when kids and pets are indoors.
- Water down or sweep up loose powder once the pests are cleared.
- Never dust into a bee or butterfly foraging zone; DE kills them too.
- Store essential-oil sprays out of reach of children. Concentrated peppermint oil is a skin irritant.
Frequently Asked Questions
What is the fastest natural way to kill an ant trail indoors?
A peppermint-oil spray wiped along the trail with a paper towel breaks the pheromone signal within an hour. The ants that arrive after cannot find their way, and the trail dissolves inside 24 hours.
Is diatomaceous earth safe around dogs and cats?
Food-grade DE is safe if a pet licks up a small amount, but the fine powder can irritate lungs. Keep pets indoors while you dust, and water the treated area gently once the pests are cleared.
Will peppermint oil damage plants or lawn grass?
At the 15-drop dilution in this recipe, no. A concentrated peppermint spray can burn tender leaves, so mist the ground around plants rather than the foliage itself.
How often should I reapply diatomaceous earth?
After every rain, and every 3 to 5 days on dry stretches until you stop seeing activity. DE only works when it stays dry and sharp.
Do these remedies work on fire ants specifically?
Yes, but with a caveat. Fire ant colonies can hold 200,000-plus workers, so DE alone takes 2 to 3 applications to clear a mature mound. Combine DE with a slow drench of near-boiling water for the fastest result.
What about vinegar or borax?
Vinegar disrupts pheromone trails but evaporates fast, so it is a stopgap. Borax mixed with sugar is effective but toxic to pets and toddlers; stick with peppermint and DE around little ones.
When should I call a professional exterminator?
If ants are inside the wall cavity, if you see more than 3 mounds within 20 feet of the house, or if bites are causing an allergic reaction in a family member, call a licensed pest-control operator.
Deborah Tukua
Deborah Tukua is a natural living, healthy lifestyle writer and author of 7 non-fiction books, including Pearls of Garden Wisdom: Time-Saving Tips and Techniques from a Country Home, Pearls of Country Wisdom: Hints from a Small Town on Keeping Garden and Home, and Naturally Sweet Blender Treats. Tukua has been a writer for the Farmers' Almanac since 2004.
- Deborah Tukua
- Deborah Tukua
- Deborah Tukua
- Deborah Tukua
Sorry to say, commercial ant traps like sticky box traps work a bit but will fail to deter others from invading homes or back yards. Pure vinegar works well but do not use it on lawns nor close to plants. I found those commercial little metal circular cans with bait to be a band aid approach, and like other voicers say, boiling water works but try to stay away from harsh chemicals that can endanger pets and young children Good luck…
Nothing works for fire ants quite like a big pot of boiling water. Two applications and they are done. After the first application you will see hundreds of dead ants around the mound. Second application usually does the trick.
Our 160 year old family home has never been plagued with termites. Why? Because ants loathe termites & we respect & coexist with the tiny ant.
We must have contented ants, as I don’t ever recall ants ever entering our home………except perhaps, for the stray ant who entered, having hitch hiked in on a picked flower.
I had several mounds around the walkway and in flower beds. I used boiling hot water to
get rid of them. Hot water will kill grass but in places where there is no grass, it works great.
I found a 50/50 mixture of borax (environmentally friendly product used for laundry and storing frozen fishing roe) mixed with icing sugar works quite well. Ants are nuisance pests, and are resilient. Sprinkle the mixture along ant paths, and on top of hills, we even put a little in the pantry and within days the little buggers are gone. Please be careful when using this idea with young children or pets around. Do not clump it on the grass as it will burn as it suffocates the spot. The ants will be gone and not reappear for several weeks. The icing sugar is the attractant and the borax will be taken down to share with the nest to destroy them. Reapply after rain periods or watering the lawn, it works…..
A few years back I had a bad case of ants on my kitchen counter…….. I just mixed equal parts of water and vinegar and sprayed the counters window sills and threshold……… In a few days they were gone, never returned……………
Boric acid power will kill sugar ant’s
The exterminator, cinnemon didn’t seem to work. Only thing that might have worked was the peppermint, spearmint, eycupliptis citris scented cleaner kept the spiders away and mice, ants-NO! They ran over the cinnimon and baking soda.
Tried exterminator,,didn’t work, I don’t know what he is using but spiders and roaches, ants are thriving like never before! They are building & escavating all around us, stirring up all kinds of varmin,,like mice also!! Daddy long legs are horrible! Anyway, baking soda sorta worked,,,for mice the glue pads are working, for ants,,cinnimon didnt work! Mint and spearmint , peppermint OILS are VERY EXPENSIVE. Hard to find. Euculiptis oil was cheaper and worked good, got it at Kroger grocery store,,found out they have it at just SOME of the stores,,it sells right away! So does peppermint oil,,goes fast! Found some tiny teeny bottles in the baking dept. I will never build in the woods, undeveloped land again!! Mice, roaches, ants, spiders, racoons and deer are a nuci
ence, they poop and eat your plants and trees,,no nature for me!
Borax & maple syrup. Worked like a charm!