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Many herbs have antibacterial, antiviral, antifungal and even antibiotic properties. Using these herbs in essential oil form (or even dried form, from your garden) allow you to create many natural cleaners inexpensively.
Dishwashing liquid - Fill a 22 ounce squirt bottle with fragrance-free castile soap. Add in 25-30 drops of antibacterial essential oil. Good options: lavender, lemon, lemongrass, orange. Use 1-2 T with each dish load.
Dishwasher powder - Combine 2 cups each of washing soda and borax, followed by 20 drops of antibacterial essential oil. Use 2 T with each dish load.
Antibacterial Oils: Bay, camphor,
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Here are some other great sites dealing with buying, storing and caring for your Essential oils: