Silver Mulch has been University proven to increase yields up to 20 percent and lowers insect problems. * Silver Mulches reflect sunlight up into the undersides of the canopy, thereby increasing photosynthesis, leading to rapid growth * Both harvest yields and coloring of fruit increased with Silver Mulch. * The extra light from the reflection repels insects and the increased light from reflection is one of the reasons your yields increase. * Silver on one side black on other.