Question: I have a clay soil (So Cal.) and want to know how many applications typically does it takes to penetrate to a depth of one foot and achieve a noticeable softening? Jeff Answer: Jeff, I would use the PENETRATE and MAXIMIZE and NOURISH with it for fastest and best results. I seem to get changes in layers about 3" at a time and those incremental changes occur about every 6-12 months. Make sure you are growing something in the area also. Plant growth is an important part of changing the soil. John