Scatter orange and lemon peels (cats dislike citrus smells), cayenne pepper, chili pepper flakes, coffee grounds, pipe tobacco, lavender oil, lemon grass oil, citronella oil, peppermint oil, eucalyptus oil, or mustard oil.
Humane deterrents are the best approach.... Smells that repel cats: To keep cats out of yards or gardens, plant the herb rue or sprinkle dried rue. Citrus or lemon scents (orange peels, lemon peels), garlic, ammonia, vinegar, coffee grinds, pipe tobacco, mustard, citronella, or eucalyptus all deter cats as well.
The second part of the outdoor cat predator problem is that cats are themselves prey. They will be killed by coyotes, eagles, owls, raccoons, dogs and otters. Two cats were killed by an otter when the cats got to close to their nest. Cars and humans also kill cats.
According to the website for the MSPCA-Angell, a nonprofit animal protection organization in Boston, most cats hate walking on aluminum foil, heavy plastic, or sticky surfaces, so if you want your cat to stop hanging out on the counter, make sure the surface is unwelcoming.
Use scent deterrents
Try orange and lemon peels, cayenne pepper, coffee grounds, lavender oil, lemon grass oil, citronella oil, peppermint oil, eucalyptus oil, and mustard oil. You can either sprinkle drops directly onto your flower beds or soak a cotton wool around it and place at entry points.
Vinegar, soap, and other household cleaners
Eye-watering vinegar-based smells are disliked by cats—as are other strong-smelling household cleaners, like soap and bleach. Because vinegar is non-toxic, it's a go-to for use as a cat-repellant and pet-safe cleaner.
Unlike their canine companions, cats hate belly rubs. Cats are protective of their stomachs as instinctively they know that this is a vulnerable area. For this reason an unprompted belly rub may result in them lashing out with their claws.
Bananas. Cucumbers aren't the only grocery which cats are unimpressed by, bananas are also a no-go. Cats have a sense of smell which is 14 times stronger than our own so strong odours like fruity scents can be too much for their sensitive snoots.
Because their sense of smell is so sensitive, it's important to be aware of things like scented litter, other animal's smells on you or an unfamiliar scent in your cat's environment (such as a new piece of furniture or a house guest). These things may upset your feline friend.
The strong smell of coffee can be enough to keep cats off of your garden. Simply take your fresh, wet coffee grounds and distribute them around your borders and plants where you want to discourage feline attention. What's more, the coffee grounds are entirely biodegradable so they will decompose and enrich your soil.
Other smells that cats don't like include the strong, acidic scent of citrus. That's because oils from citrus fruits like oranges, lime, lemon, and grapefruit are toxic to them (7, 8, 9, 10), says Koski.
Cats find the smell of citrus fruits horrid, in particular, oranges and bitter apples. As citrus is usually a pleasant scent for us humans, we can use this to our advantage by using the smell to keep our fur babies away from where they shouldn't be.
Cats are fastidious animals that spend a great deal of their day grooming themselves. Wet fur is extremely uncomfortable for a cat and often takes a long time to dry. Wet fur is also heavier than dry and thus makes a cat less nimble and easier for predators to catch. There is also the shock factor.
Spraying your cat with water can make her uncomfortable
Spano explained. “[So] equating the discomfort a human feels upon being spritzed with water to the discomfort a cat feels upon being spritzed with water is unfair and not rational.”
Explanation: It is a cat's natural instinct to dig and deposit in soft or loose soil, moss, mulch or sand. Quick Solutions: Scatter fresh orange and lemon peels or spray with citrus scented fragrances. Coffee grounds, vinegar, pipe tobacco, oil of lavender, lemongrass, citronella or eucalyptus also deter cats.
"Cats are genetically hard-wired through instinct to avoid snakes," Con Slobodchikoff, animal behaviorist and author of "Chasing Doctor Dolittle: Learning the Language of Animals," said. "Cucumbers look enough like a snake to have the cat's instinctive fear of snakes kick in."
The mystery of why cats hate cucumbers is normally explained by the natural fear cats have towards snakes. To a feline's eyes a cucumber can look similar enough to the pesky reptile to elicit their fear response and make them jump a few feet in the air to avoid being bitten.
Macavity a.k.a. the Mystery Cat – A notorious criminal known as the "Napoleon of Crime".