What to Do If PH Is Correct But Plants Are Still Getting Deficiencies

by Nebula Haze

Example of a sick cannabis leaf that is pale yellow and has markings from what appears to be a nutrient deficiency, even though the pH at the roots is right!When I was first learning about how to grow cannabis, I learned about the importance of pH to prevent nutrient deficiencies.

Basically, when it comes to cannabis plants, your plant will start experiencing nutrient deficiencies  if the pH is too high or too low at the roots! This is because the chemical structure of nutrients actually changes at different pH levels, and some version are easier for the plant to absorb than others.

By giving your plants good cannabis nutrients and managing the pH, you'll be able to prevent most nutrient deficiencies, ensuring your plant grows as fast and healthy as possible!

But what do you do if you're using good nutrients and the pH is right but you're still getting nutrient deficiencies?

When it comes down to it, nutrient deficiencies usually start at the roots, whether it's pH or something else! This looks like a nutrient deficiency, but it's actually caused by overwatering!

Example of a cannabis plant that's got a nutrient deficiency due to overwatering

One of the most common reasons to see deficiencies when the pH is correct is the plant is being over or under watered, which can also be related to the drainage of the grow medium and the container your plant is is. When the plant isn't getting the right ratio of water and air at the roots, it will tend to start showing deficiencies even if everything else is right!

Causes of Most Nutrient Deficiencies

Note: Basically anything that makes your plant droopy is likely to cause nutrient deficiencies, too!

Although pH and watering practices are probably the most important thing to pay attention to, there's more than just pH as far as your plant roots are concerned. The "alkalinity" of your water is also important. Alkalinity is related to pH, but it is also it's own thing. In a way alkalinity measures how much "stuff" is in the water that causes the pH to go up. And this also affects nutrient absorption.

If you're still having trouble after going through the steps above, and your pH is in the right range…

  • If you have "hard" water, you should generally aim for a slightly lower pH (aim for around 6 pH for soil and 5.5 pH for coco or hydro).

  • If you have "soft" water, you should generally aim for a slightly higher pH (aim closer to 7 pH for soil and 6.5 pH for coco or hydro).

I hope that helps some people dial in the correct pH based on their starting water!



Jump to…

Tips to Growing Top-Shelf Buds

How to Measure & Adjust PH

Which Nutrients Should I Use?

7 Steps to Fix 99% of Growing Problems




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