Keep slugs and aphids away with a homemade, nonchemical pest spray. Place one peeled onion, two peeled garlic cloves, and one teaspoon cayenne pepper in the jar of a blender. Add three cups of water, and blend until smooth. Let the mixture sit overnight, strain the liquid into a spray bottle, and coat plants generously. The solution will keep, refrigerated in the bottle, for up to one week.
Pest spray from natural ingredients. "I have been making this spray for more than 20 years--I don't remember where the idea came from--perhaps an old issue of Organic Gardening or Mother Earth News. I do know that the recipe works. "