How do foliar sprays increase brix readings?

A good foliar spray will include phosphate in its nutrient package. Phosphates are the energy source in ATP. ATP drives the Krebs cycle in plants. Increasing phosphates in the plant through foliar spraying allows the Krebs cycle to transfer more energy within the plants. This allows the plant to be more efficient in storing energy as sugars from the process of photosynthesis. Some of these additional sugars are sent down to the roots and excreted out of the roots as exudates. Root exudates are a food source for bacterial colonies around the roots. The bacteria respond to the extra food from the plant by making more minerals available to the plant. The additional minerals are taken up into the plant and increase the total dissolved solids in the plant. This registers as a rise in brix.  more