Testing Cat Deterrents
My experience of cat scarer and repellent products
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Cats are very territorial and when introduced to an area, they will try to “own” land by displacing other cats. They usually attempt this by prowling, intimidation, hissing and as a last resort, by fighting.
The cats within a given area then form a hierarchy, it’s not unusual for one cat to roam a specific area at a certain time (ie early evening) only to give way to another cat later on during the night.
The relationship between cats and the land they roam on is complex, constantly evolving and barely understood. There is one thing is for sure though; putting up a fence or hedge won’t stop a cat from coming into your garden and unlike dogs, cats can’t be taught to stay out of an area.
The good news is that there are several cat repellent products that work and I know, because I’ve tested them.
I’m confident that these products will stop cats doing certain things, for example, digging in flowerbeds, climbing fence posts or traversing fence panel tops.
I’ve made my garden less attractive to cats, and I’ve seen less damage from them.
While it’s unlikely that you’ll be able to stop every cat from coming onto your property, research has shown that some cat deterrent products can reduce cat activity by 46% and by using several products, you can expect even better results.
An experiment in Australia revealed that ultrasonic cat deterrent devices reduced the number of cat incursions into the test area by 46% and the amount of time cats stayed within the test area dropped by 78%.
– Research discovered by our Fact Checker Paul Farley – (link to research paper)
Wall, Fence and Post Spikes
Wall and fence tops are often used by cats to not only traverse from one garden to another but I’ve sen them perch where they can keep an eye on the nearby territory.
These plastic spikes are affordable, humane and I found them easy to fix in place and they work. Just screw them down into the top of the fence or wall.
If you’ve noticed a cat using a fence post to gain access to the fence top, you can easily secure these cat deterrent spikes vertically along each side of the post as well.
I’ve also seen gardenrs secure them to the sides of brick walls at strategic locations where cats are likely to climb.
You may need to monitor cat movements after installing these and then make adjustments as cats are very smart and quite capable of solving simple puzzles and creating workarounds.
- They last for years, I still see them on the fence at my old home that I moved out of 5 years ago.
- I’ve used them on both fences and wall tops.
- They actually work.
- Burglars won’t like them either.
- Requires some effort to install.
- Not practical for gardens without solid boundaries.
- You could potentially need dozens or hundreds of metres of spikes.
My Experience With Wall Spikes
I first came across fence spikes when I was working for a customer who had a fish pond and I asked him if they were effective, he told me they significantly reduced the number of cat intrusions into his garden.
More recently, I used these at my previous property and can confirm that cats will not walk on them and they won’t perch on fences on walls if these spikes are fitted.
I did notice that some of the cats started to jump over the spikes so they aren’t a silver bullet solution.
“No Dig” Soil Spikes
The team here at DIY Gardening often plants new flowerbeds, fruits and vegetables etc. After turning the soil over and adding compost we are always paid a visit by a cat who leaves us a little present, usually deposited in a shallow hole.
To deter cats from digging and pooping in your flowerbed or vegetable crops, you could try covering the area in “do dig” soil spikes.
These plastic spikes are cheap and easy to lay, you can also use them again should you redesign the garden at a later date.
While they might not be practical for large areas, they are certainly suitable for small flowerbeds, pots and areas set aside for vegetables.
These spikes are humane in that while the cat will find them uncomfortable they won’t cause any harm.
With a little creativity, you can also use these spikes to deter cats from climbing tree posts.
My Experience With Soil Spikes
I used these spike mats about 8 years ago and they had a slight effect in the flowerbeds but I found them very effective at keeping cats out of my large containers that contained bulbs to which the cats were attracted.
If you’re having issues with cats or squirrels digging into large pots and containers, you can bury these into the compost but you may need to jerry-rig them so the pests don’t claw them out.
Ultrasonic Cat Repellents
In addition to the Australian research that showed these products reduce cat intrusions by 46%, the UK’s RSPCA organisation revealed that they can reduce the number of cats entering an area by 32% (source).
Unfortunately, this data also suggests that 68% of cats don’t respond to ultrasound cat repellent products at all.
The device uses a motion detector which then activates an ultrasonic emitter. Only cats, foxes and some dogs can hear the noise and the frequency is outside the detection range of human hearing – I certainly couldn’t hear it.
While I do recommend this products, it will only help to reduce, not entirely prevent cat intrusions.
In my experience, you should also relocate the devices every week or so as the cats seem to get used to them and are no longer startled.
What I Like
- Research has proven that they do work.
- I found it easy to set up in seconds.
- Not affected by the weather.
- Up to 12m range.
- Effective, for a while at least
What I Don’t Like
- Requires batteries that will need to be replaced/recharged.
- When I used these cat repellents, I found that our dog could hear the noise too.
- During testing, I discovered that the cats in my area got used to it so I had to relocate the device every week or so to maintain the “shock” effect.
My Experience With Ultrasonic Cat Repellents
I tested cat ultrasonic repellents at my previous property as my garden was frequented by a few cats that left surprises for me in the flowerbeds and one in particular that loved digging out my containers.
During the testing period, I discovered that the scarers initially worked very well within a range of about 10 metres.
I witnessed first-hand how the cats were startled and alert whenever they came into the garden and I noticed a reduction in the number of intrusions.
Unfortunately, after a few weeks, the number of cat visits increased – I believe they had become used to the noise and were no longer startled by it.
I experimented by relocating the devices and the cat visits reduced again for a short time.
In my experiment, I never reached zero visits but by relocating the devices every couple of weeks or so, I was able to significantly reduce the number of visits and the duration of each visit.
Motion Activated Repellent Water Sprayers
If you want to startle unwanted animals that enter your garden, this is by far the best product I’ve tested.
The motion detector has a dial so you can easily adjust the sensitivity; target larger animals such as foxes or smaller pests such as cats.
Once activated, this device will detect movement and then spray a jet of water at 260° which is more than enough to scare away animals.
You’ll need to replace the 9-volt battery every three to four months and this sprayer only works if you have good water pressure – you’ll also need to attach it to a hose.
The Scarecrow motion-activated sprayer takes only a few minutes to set up and protects your garden day and night.
Unfortunately, the device cannot tell the difference between welcome guests such as humans and dogs and pests such as cats and foxes. You may get a little wet setting up this product and if you have a dog, they’ll either love it or hate it.
Use sprayers like this in parts of the garden you don’t use often, it’s not a product you can deploy near the front door or any other area where humans use frequently.
There are several products you can choose from. The Scarecrow is one of the better ones but will only work with good water pressure and you may need to upgrade the connectors which may leak slightly (Hozelock connectors are available in most DIY stores).
My Experience With Sprayers
I purchased this product with a view to testing it but unfortunately, I discovered that my water pressure was far too low to activate it so I don’t have any first-hand experience to share with you.
I did see this sprayer in action several years ago when a customer I was working for had one installed at each end of his large koi carp pond. I asked the owner how effective it was and he stated that it was primarily used to keep birds of prey away from the pond but also worked well on cats who sprinted off when the water hit them.
I believe there are two alternative products worth considering:
I used several different odour gels and granules including citrus pellets, lion dung and several others.
These all produced a pungent smell that is supposed to deter cats.
I discovered that they did work when I placed them in my pots and containers but in the garden border they did nothing and I found that they had no effect on the number of cat visits and the duration of the visits.
I have seen one garden where the owner fixed roller bars to the inside of the fence to stop his house cats from escaping.
I asked him how effective they were and he told me that neither of his two cats have ever escaped.
Roller bars are primarily designed to keep animals in the garden rather than out, but they will work if placed on the other side of the fence. That will only be possible with the permission of the landowner on the other side of the fence.
Cat Repellent FAQs
Can I take legal action against a cat owner?
Cats have a right to roam and unlike dogs, their owner is not expected to keep cats under strict control.
There is no law that punishes cat owners for cat fouling or trespass. There are, however, several nuisance and anti-social behaviour laws that can hold cat owners responsible for aggressive behaviour and damage to property.
Answers to more cat-related legal questions can be found here.
What's the easiest way to scare a cat from my garden?
I’ve found motion-activated water sprayers to be the most effective product, they scare cats and foxes who rarely return to the garden
Can lion's dung put off cats?
I’ve tested products that contain lion’s dung, a strong scent that reportedly scares off cats, and the results so far have been inconclusive in large areas. They only work in containers and they need to be replaced.
Do sonar or ultrasonic cat repellents work?
Research has revealed that after deploying garden ultrasonic cat deterrent devices, cat activity reduced by around 32%. Many cats, but not all, will be deterred by such products.
Meet The Author: Daniel Woodley
Daniel has over 18 years of experience in the construction, home improvement, and landscape garden industries.
He previously worked as a project manager and has experience in managing teams of tradespeople and landscape gardeners on both small and medium sized projects.
Daniel is also a keen gardener and enjoys growing unusual plants and tending to his lawn.
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