Here's what FoxFarm recommends as a schedule for feeding when using their products. I have used it and it performs very well, but remember that each garden and strain is different. there is a printable version of this schedule available at http://www.foxfarmfertilizer.com/
Originally Posted by Fox Farm
soil and soiless feeding tips: Use FoxFarm Ocean Forest potting soil when transplanting into larger containers. For best results feed with every other watering. During the flowering stage reduce the amount of light from 18 hours to 12 hours. Maintain a PH of 6.3 to 6.8 to prevent nutrient lock out and reduce stress on plants. Use primary nutrients for abundant growth and stocky, robust plants. For high octane yields add supplements to the weekly diet. Never mix pure concentrates together. always add water first.
Use Fox Farm BushDoctor SledgeHammer combined with Big Bloom in conjunction with other FoxFarm nutrients to relieve plant stress, unlock unwanted salt bonds and allow for increased nutrtional flow. Note: In coco this process is especially helpful, as coco has a tendency to retain mineral salt build up
For longer grow cycles, continue the week 12 feeding schedule until harvest.