In the first 25 to 30 days of cherry fruit development, after full bloom, every cell in the skin of the cherry is formed. If you do not have the correct nutrients in the skin as it is formed, then you can get rain induced fruit cracking. These nutrients are not mobile in the plant, so they cannot move from one cell to another. It is very important to provide these nutrients as the cells are being formed. The nutrients that help prevent rain induced fruit cracking are in the Resistor product. Go to resistor2150.com for the complete cherry program.