Yes. You can use your pH/EC meter to help you fine-tune, but categorically you’ll be delivering nutrients customized to meet the changing demands of the crop throughout its growth stages. Below is an example of a nutrient schedule that reflects how these needs change as your plants grow and mature:
Seedling or Cutting: 1-1-1 balanced formula at about 100 ppm for each once of soil
Vegetative Growth: About 200 ppm N, 120 ppm P2O5 and 200-250 ppm K2O
Early Bloom: Extra calcium and magnesium, about 200-250 ppm N-P2O5-K2O with a little boron and potash, slightly reduce nitrogen if plants are large
Late Bloom: Reduce N applications to about 125 ppm, check phosphorus, use about a 1 to 1.5 ratio of N to K2O, potassium silicate (optional to strengthen plants)
Flush: Monitor pH and EC, feed only water once every 10-14 days, depending on EC readings
Your fertilization rates can also change depending on the type of growth medium you are using and depending on the quality of your water. Different varieties (strains) of plants can also have individual preferences.