I don’t get it, My last watering was water and cal/mag only. Run off was ppm 159 and PH 6.6.
Eleven days later I watered plant with 3gal of RO 10ml cal/mag, 10ml micro and 20ml bloom. PH of solution was 6.2 and EC was 1.4. Run off numbers are PH5.8 and EC 4.0.
Whats obvious is soil is over nuted, but how?
How did I end up with the numbers that I did on my latest watering (EC4.0, PH5.8)?
I found this, How to Manage Run-off EC
“It is important to provide nutrient solution that is the correct EC, but the EC rises as the water sits in the pots. As a result, root zone EC is generally higher than inflow EC. Because EC gradually rises as the nutrient solution sits in the pots, fertigation frequency is one of the main ways that you need to manage the EC of the nutrient solution in the root zone. If the time between fertigation events is long, then the difference between the EC of the inflow and the EC of the nutrient solution in the root zone will be large.”
Unfortunately the article doesn’t explain why EC rises as solution “sits in pots”
So how does EC magically rise by nute solution just being present in the medium?
If you do any cooking, the rising EC could be compared to “reducing” a sauce in a pot on the stove. The water evaporates off but the solids are left in the pot.
Waiting 11 days between watering will do it. That will really give the water a lot of time to evaporate and be transpired by the plant, leaving the solids behind in your roots.
It is also the reason for EC rise after long dry periods, to answer your second question.
Having thought about this for the day I may have added nutes too soon.
I pre-saturated to a significant run-off, this medium before
transplanting to get the ball rolling. I would have thought that would have leached away any starter charge it had. Looks like I was wrong.
