Harsh Chemicals or Natural Products
Historically, the weapon of choice for homeowners and their mold cleanup battles has been bleach. Today, many find vinegar equally effective in mold abatement. Tea tree oil mixed with water is also a handy natural alternative, as is grapefruit seed extract mixed with water. These products are pricey compared to vinegar, but keep in mind that they are only needed in small quantities. Normally, only a teaspoon or two are needed, mixed with 2 cups of water. Lots of people use these inside the home in areas where vinegar may cause damage to the surface they are trying to clean; for instance, marble is a material that can be damaged by vinegar.
Since a garage mold cleanup project may be quite large, economical options here are preferred. Borax is one such cost-effective choice. Borax contains elemental boron which is used in many commercial applications for pest and fungicidal control. Borax can be found in your local supermarket in the laundry section, and a simple water-borax solution can be very effective at mold cleanup.