Cats dislike eucalyptus, lavender, lemongrass, and peppermint – just choose the ones you don't mind the scent of yourself.
Cats are more sensitive to scents than humans, so essential oils with strong odors, such as citrus and lavender, can help repel them. You can substitute lime, peppermint, and/or eucalyptus for the lemon, wild orange, and lavender if you prefer.
As a general rule, cats are sensitive when it comes to smells, but there are a few scents they hate that might just surprise you. They can't stand citrus and as much as you might love the smell of fresh herbs, cats hate rosemary and thyme. Banana and mustard are a big no-no too, as well as lavender and eucalyptus.
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.
Orange and lemon peels (cats dislike citrus smells), cayenne pepper, coffee grounds, pipe tobacco, lavender oil, lemon grass oil, citronella oil, peppermint oil, eucalyptus oil, & mustard oil.
Cats dislike the smell of certain scents, such as citrus, eucalyptus, lavender, peppermint, and rosemary. You can use these scents to deter cats from entering certain areas of your home or garden by using essential oils, planting these plants, or using citrus peels.
Squeeze 2 drops of lemon essential oil, 2 drops of wild orange essential oil, and 2 drops of lavender essential oil to the bottle. Cats are more sensitive to scents than humans, so essential oils with strong odors, such as citrus and lavender, can help repel them.
Essential oils that are unsafe for cats:
Citrus oils (bergamot, grapefruit, lemon, lime, orange, tangerine) Birch.
Lavender, geranium, and eucalyptus
Some gardeners use lavender plants to deter deer, but you can also try this as a deterrent for felines. Likewise, geranium and eucalyptus plants give off an odor that cats dislike.
Peppermint oil is highly toxic to cats.
Without the enzymes required to break down phenols, cats exposed to peppermint oil can experience: Liver damage. Breathing difficulties. Wobbliness and seizures.
Many veterinarians and other pet care experts recommend not using tea tree oil for cats, even though it has been considered a safe and effective remedy for some feline complaints in the past. Tea tree oil is one of several essential oils, such as peppermint oil, considered toxic to these animals.
Some of the most popular essential oils for odor control are as follows: lemon, lemongrass, rosemary, lavender, tea tree, and orange. You can choose one, or create your own unique blend using your favorite oils!
While a lavender plant itself isn't toxic to your cat, formulations from the plant can be. Your cat can eat a lot of lavender and may suffer only an upset stomach, but on the other hand, lavender essential oil can be deadly for your pet because of its concentration.
Toxicity to pets
Small ingestions of a few leaves or low concentration eucalyptus oil leads to mild gastrointestinal distress, but ingestion of highly concentrated eucalyptus oil has been associated with severe signs including seizure, tremor, and, rarely, acute renal injury.
Vinegar as a cat repellent
Spraying Outdoors – Straight or diluted vinegar can be sprayed around the edges of a garden, and on plants, fences, posts and garden décor to keep cats away. Concentrate the spray on areas that the cats frequent or that you particularly want to protect.
In a spray bottle, mix 16 ounces (about 500 ml) of warm water with 10 drops of peppermint essential oil or two tablespoons of peppermint extract. Spray all of the areas that you think your cat may have urinated or marked. Within a few hours the scent will be gone.
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. One sniff and they'll be gone.
You should avoid using peppermint and lavender essential oils as they can be harmful to the cats. Mix one part essential oil to three parts water in the spray bottle. Spray in areas that you want to keep cats out of. Reapply daily or as needed.
Lemongrass oil is most often found in the form of a hydrosol, a 100% non-alcoholic aroma that is made by steam-distilling or hydro-distilling plant matter. Lemongrass is a safe essential oil to use around cats at a low concentration. It should not, however, be ingested by cats or directly applied to their skin.
Lemongrass isn't harmful to cats, as long as they nibble in moderation. When made into an essential oil, lemongrass is potentially deadly for your cat. All cats lack glucuronyl transferase, a liver enzyme, that helps to break down most essential oils, including lemongrass.
Signs of lavender toxicity in cats include diarrhea, vomiting, and weakness. However, your cat may also experience respiratory symptoms when inhaling lavender essential oils, including coughing and wheezing.
Lavender
Cats seem to hate the smell of lavender since the strong scent can be too much for them. Lavender plants can also be used as a natural repellent in your garden for cats.
Lavender seems to be the best researched essential oil for use with cats when diffused. Although scientific evidence supports its calming effect on cats when diffused, it can still be toxic if applied topically neat or undiluted to your cat's skin or fur, as can any essential oil if undiluted.