We have a vintage aluminum Christmas tree and I was SURE the cats would see it as a feast, so I took a LOT of precautions the first time we set it up. I doused the whole bottom of the tree with Bitter Apple spray (and as other have said, do NOT get it in your mouth, it stays FOREVER. Also, don't inhale while you're actively spritzing as I've gotten the taste in my mouth that way). I made little "ornaments" of cotton balls dredged through Vicks Vapor Rub and hung a bunch of those from the lowest branches. So far it's kept them from even testing it out! You could try rubbing the Vapor Rub along the chord; it smells pretty potently, but I'd think it would taste pretty nasty too.
Bitter Flavor Sprays and other Taste Deterrents for Pets - Pets WebMD
Also, is it sticky? Since I am going to be spraying it on electrical cords, I don’t want a sticky mess that is going to get on the carpet and walls. Has anyone had success with using bitter apple spray for their dogs or cats?
Bitter Apple -- is it for cats, dogs, or both
Siouxsie: Bitter apple spray is an old standby. Again, the nasty taste is supposed to stop cats from chewing on wires. Other options include Vicks VapoRub, Tabasco sauce, rubbing the wires with a moistened bar of soap, or using double-sided tape to make cord chewing extra-unpleasant.
Questions about the use of bitter apple spray - The Daily Kitten
Atticus, my half cat/half dog, has been chewing on a few electrical cords around the house. I am only finding bitter apple spray for dogs…can it be used for cats, too? Adam must have been desperate to be tempted by the apple and so was I when I picked up Bitter Apple. My five precious cats were clawing, climbing and chewing my near equally precious house plants. I had also been limited in plant selection to only non-toxic ones.
Over the years I had tried many ways to remedy the problem of cats living with house plants. Some worked but were messy concoctions I had to prepare in the kitchen and others didn't work at all. So when I saw Bitter Apple on the store shelf, I took the lid off and tested it right there on my own tongue. YUKK!! said my tongue, this has GOT to work on those pesky cats.
I sprayed Bitter Apple on all of my 40 or so plants and much to my surprise and chagrin all of my cats, though none are named Mikey, liked it. My daughter wanted to try it on her plants/cats and ditto for her experience. That's a total of eleven related and unrelated cats. They all seemed to love the taste and went after our plants worse than ever.
I finally did find a remedy that works well. I keep two sweet potato vines growing in individual containers for the cats to graze on. They love the vines and stay away from my other plants. I still don't risk growing toxic ones though. You just never know with cats which could be the bitter pill Bitter Apple has to swallow on this one.