Cats do not like citrus. More precisely, their flavor. To your cat lost any interest in the indoor plant, sprinkle the pot and ground in it with a spray with the smell of lemon, orange or put in a pot pieces of orange or lemon peel.
Pepper against cats. You can buy special sprays based on red pepper, but never spray it on a cat, it's enough to sprinkle the soil in a pot.
There is a special spray "Bitter apple", which for a long time will beat your animals desire to eat what is not allowed.
Foil and plastic protect the houseplants. From the foil you can make special mini-obstacles in the way of cats to pots with flowers. The rustling of the foil can scare away the animal, well, if it's from fearful ones.
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