Castor Oil for Gophers: Repellent Recipe & Guide

Castor oil for gophers

Gophers are the scourge of lawns and yards all over North America, meaning there are multiple ways people advise you can use to get rid of them. One of the more popular responses you will get is to use castor oil as a gopher repellent. 

But just what does it do and how do you use castor oil to repel gophers? All you need to know is laid out below including a recipe and “how to” guide.

How to get rid of gophers with castor oil

Liquid castor oil has been used to get rid of gophers for decades, and it’s even used in professional pest control pellets and granules you can buy on Amazon

There’s good reason why it’s in off the shelf products: it has a strong odor which is an unpleasant smell to gophers. If ingested, it will also give gophers diarrhea, so they want to get away from it.

To use castor oil to repel gophers you will need to spray a special mix recipe near the entrances to their tunnels, down their holes (if open), and near plants they are feeding on.

Here’s what you need, followed by the recipe and instructions.

Castor oil recipe for gophers

  1. Mix a ¼ cup of water with 2 tablespoons of dish soap liquid.
  2. Stir it until it goes a bit foamy.
  3. Mix it into a gallon of water and mix it all up.
  4. Pour the mix into your gallon sprayer.
  5. Spray around the gopher holes and areas.

As an alternative you could buy castor oil granules on Amazon. The ones I linked to earlier say they have a secret method to penetrate the soil better. How true this is I don’t know, but if you click the image of the product below it will let you read the Amazon reviews.

Be aware the castor will quickly wash away from lawns. Based on that, I recommend you spray it weekly, even after the critters have gone. This could help ensure that gophers are not tempted to come back and stay away from your yard.

Does castor oil really get rid of gophers?

As part of the research into this guide, I used castor oil in my brother’s backyard when he had a gopher hole appear. Castor oil did repel the gopher on his property, and a month later it had not returned.

Obviously, that’s not the most scientific approach, but I am not a scientist. So, instead I asked on a gardeners Facebook group if they had success using castor oil as gopher repellent.

I had 7 responses, and the replies broke down like this:

  • 2 said it worked.
  • 2 were not sure as they used other methods at the same time.
  • 3 said it did not work for them.

Based on that, it’s inconclusive as to how effective castor oil is on gophers.

However, my advice would be try using castor oil, whether that’s liquid form, pellets, or granules, and see how you get on.

What is worth bearing in mind, is that best-selling gopher repellent on Amazon has castor oil as a base ingredient. 

I think that tells you what you need to know. You can buy the repellent on Amazon. It comes in granules which help the castor oil penetrate the ground to be more effective against gophers. 

Handy Hint: Read my guide to getting rid of gophers and how to fill their holes if you want to try alternatives to oil.

Is castor oil harmful to pets?

Potentially toxic to dogs and cats if they ingest it orally, and by that, I mean drinking. Truth be told, your dog or cat might lick some castor oil off the lawn, but it should not do them any harm at such a small quantity.

If after using castor oil as a gopher repellent in your backyard, you notice your dog has diarrhea, it could relate to them licking it. Castor oil can act as a laxative to dogs. 

The bottom line is, if you see anything unusual, no matter how trivial, speak to a vet. 

Will castor oil kill grass or plants?

The next concern you might have will be whether the castor oil you used for gophers is going to harm the lawn, grass, and plants in your backyard. 

The simple answer is no. Castor oil is a natural pesticide that will not kill or harm grass. It might make it shiny for 24 hours or so, but other than that, it should not do damage to your lawn – unlike gophers

Also, you might have read that castor oil contains ricin, which is renowned as being extremely toxic to humans and animals. However, don’t panic, the ricin is removed during manufacturing (according to the CDC):

“Castor beans are processed throughout the world to make castor oil. Ricin is part of the waste “mash” produced when castor oil is made.”

How much castor oil does it take to kill gophers?

Some of you reading the last section might think that’s a shame, as if the ricin wasn’t removed, there’s a chance castor oil could kill gophers. 

However, castor oil can’t kill gophers (unless you drown them in it). It’s a pest repellent only as critters don’t like the smell and it can give them diarrhea. 

Does castor oil harm soil?

Based on the quantities of liquid castor oil you will use as a gopher repellent; it will not harm the soil around your plants. You will either be spraying it in your yard or using pellets and granules during the process.

If you were pouring gallons of castor oil down gopher holes and over your lawn, I might have a different opinion.

Ultimately, castor oil for gophers is a non-toxic, so safe pest control method that has little to no effect on the quality of your backyard’s soil. 

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