Either use chemicals - or (more eco-friendly) introduce Spiders and insects to prey on the flies.
I really need to know the answer to this for my daughters homework, does anyone know who to stop FLIES and SLUGS?
Fences , or move the plants.
pepper
they are having a little sleep
Flies are consumers as producers are normally plants because plants can live without eating any other living thing/animal
spray them with chili
Thorns and a foul taste.
plant horse repelling plants around the bush
it will stop you from eating poisonous plants
Some desert plants have spines or thorns, some have a bad taste and some are toxic if eaten.
For indoor plants, try spraying a little vinegar in the soil. I know that for outside plants, you can drop mothballs around them to keep cats out.
There are different ways to stop this, but one way is to grow grass inside little window pots for your cats to eat. Encourage them to eat this grass and praise them when they do, and when they eat the other plants spray them with water or hit them lightly on the hip to discourage them from eating those plants.