How to Eliminate Ground Moles Using Dawn Dish Soap & Castor Oil

An easy, safe, and humane solution to reclaim your garden

When we first noticed the tell-tale ridges weaving their way through the lawn, I thought it might’ve been a neighbor’s dog digging or maybe the kids being overly enthusiastic with the hosepipe. But a closer look revealed fresh molehills—and a whole network of tunnels just under the surface. One determined mole had turned our yard into a miniature minefield.

Rather than rush to buy traps or chemical pellets, I did what any curious gardener would do: looked for a safe, natural remedy that wouldn’t harm the garden—or the mole. That’s when I came across a tried-and-tested DIY solution using Dawn dish soap and castor oil. I gave it a go… and it worked like a charm.

Here’s how you can do it too.

🧪 What You’ll Need

You probably already have most of these ingredients in your home. This mix is safe for pets, children, and plants, and best of all—it doesn’t hurt the mole either.

• 2 oz Dawn dish soap (the classic blue version works best)

• 4 oz castor oil

• 2 quarts warm water

• A garden sprayer or watering can

• Measuring jug and funnel (optional but helpful)

🧴 How to Make Your Mole Repellent

This method doesn’t require fancy equipment or complicated prep. Just follow these steps:

1. Mix the Ingredients

In a large jug or bucket, combine:

• 2 oz Dawn dish soap

• 4 oz castor oil

• 2 quarts (8 cups) of warm water

Stir it all together thoroughly. You want the soap and oil to emulsify with the water, creating a consistent mixture. If you’re using a spray bottle or sprayer with a narrow neck, a funnel makes pouring much easier (and less messy).

Clive’s Tip: Warm water helps the oil and soap blend more easily. Cold water tends to separate quickly.

2. Apply It to the Lawn

Transfer your mix into a garden sprayer or watering can. Then, spray the solution generously across the entire lawn—especially in areas where you’ve seen mole activity, like fresh mounds, tunnels, or soft soil.

It’s best to do this in the evening, when moles are more active and the sun won’t evaporate the mixture too quickly.

Be thorough! Make sure to soak the soil—not just mist the grass. You want the mixture to penetrate down into the mole tunnels where it’ll be most effective.

3. Soak the Molehills and Tunnels

Use any leftover solution to directly drench molehills and known tunnel entrances. Pour slowly to allow the repellent to seep deep into the soil. This is key—it’s the scent and taste that drive the moles away, so you want it to linger where they’re nesting and feeding.

Repeat the process every 1 to 2 weeks, or after a heavy rain, until mole activity stops.

🧐 Why This Works (Without Harming Anything)

The magic comes from the castor oil. It doesn’t kill the moles—instead, it irritates their digestive system and makes the soil taste and smell unpleasant. This encourages them to pack up and move elsewhere.

The Dawn dish soap acts as an emulsifier, helping the castor oil bond with the water so it doesn’t just float on top. It also helps the mix cling to soil particles, so it stays active for longer.

Good to know: This method won’t hurt your plants, grass, or beneficial insects. It’s non-toxic, biodegradable, and eco-friendly.

🔍 How to Know If You’ve Got Moles (Not Gophers or Voles)

Before you mix up your solution, make sure you’re actually dealing with moles. Here are some key signs:

• Molehills – Mounds of loose soil, usually round or oval, with no visible hole.

• Raised ridges – Long, shallow tunnels just beneath the lawn surface.

• Soft spots underfoot – The ground gives way when you walk across it.

• Patches of dead or yellow grass – Caused by tunnels disturbing the roots below.

Not sure? Gophers create crescent-shaped mounds with a plugged opening, while voles chew visible plant roots and stems.

🌿 Are Moles All Bad?

Here’s the twist: moles aren’t entirely villains. While their tunneling can make your lawn look rough and uneven, they do offer a few benefits:

• Soil aeration – Their tunnels break up compacted soil, helping water and nutrients reach plant roots.

• Natural pest control – Moles feed on grubs, beetles, and lawn-damaging larvae.

But if they’re digging through flower beds or tearing up your lawn, it’s understandable to want them gone. And this method helps you do that—without harming them or the planet.

🛠️ Other Natural Methods to Try

If the Dawn and castor oil method doesn’t do the trick on its own, consider pairing it with these additional strategies:

• Vinegar Spray: Mix equal parts vinegar and water and spray into tunnels.

• Marshmallows: Some gardeners swear by dropping marshmallows into the tunnels—they dislike the scent.

• Boric Acid: Use sparingly and cautiously; saturate only in active areas.

• Traps: Physical mole traps can be effective but are more involved and should be used carefully and humanely.

🌼 Clive’s Tips for a Mole-Free Lawn

• Spray after watering or rain – Damp soil helps the solution soak in deeper.

• Be consistent – Reapply every week or two if mole activity continues.

• Use garden markers – Mark active tunnels so you know where to concentrate your efforts.

• Don’t panic – A few molehills don’t mean an infestation. Stay calm and treat as needed.

• Stay humane – The goal is to gently encourage moles to move on—not harm them.

If moles are turning your lawn into a patchwork of hills and ridges, don’t reach for poisons or traps just yet. A simple mix of Dawn dish soap and castor oil can do the job effectively and humanely. It’s cheap, easy, and safe—and it lets you enjoy your garden again without guilt or chemicals.

Give it a try, and you might just find yourself recommending it to your neighbors, too.