This is a really cheap and natural pesticide that will keep your plants and trees free of pests.
In a small pan place three cups of water. Add two tablespoonfuls crushed garlic, half a cup crushed dry parsley. Boil the mixture until there are only two cups left. Strain in a container and let the liquid cool. Put it in a plastic spray bottle and spray the trees, plants or vegetables. It is effective against a large number of insects and apart from being cheap it is totally harmless to your health.