The Pre-Plant mix is critical for success. The Pre Plant contains Lime, Epsom Salt (Magnesium Sulfate) and Boron in a 80-4-1 ratio. If you live in a area which receives LESS then 18 inches of rain per year you would use Gypsum instead of lime. Pre-Plant is mixed in PRIOR to planting seedlings OR seeds at the rate of 1 oz per linear Bedfoot. It is recommended that you apply a new application of Pre-Plant every 60 days to an already existing garden. When planting seedlings you would add 1/2 oz of weekly feed AND 1 oz of Pre-Plant IF you are planting seedling. If you are planting seeds JUST ADD the Pre-Plant.