It’s important to maintain the pH of your root environment to prevent nutrient problems.
The easiest way to do that is to test the pH of your water before you water your plants or add water to your reservoir.
There are certain types of grows (such as when growing cannabis in organic composted super soil) where you don’t need to test your pH unless you run into problems. This is because with a properly composted super soil, you actually have a microbial colony living in the soil that will take care of the pH and hand-deliver the nutrients to the roots of your plants for you. However, this is a rare exception to the pH testing rule, and almost all growers need to regularly test and maintain pH for a successful grow. If you’re not growing in super soil that you have amended and composted (or purchased) yourself, testing and maintaining pH is a MUST.
Some growers will always get lucky and successfully grow weed without testing the pH of their water, but most people who don’t test for pH will start seeing signs of nutrient deficiencies and other nutrient problems.
If the pH at the plant roots is too high or too low, your plants won’t be able to absorb nutrients properly.
Even if plants do fine in the vegetative stage, cannabis plants tend to be more picky and prone to problems in the flowering/budding stage. Many growers have written in to tell me they got all the way to the flowering stage without testing pH, then were surprised that they start running into nutrient problems as soon as the plants start budding. In order to make sure this doesn’t happen to you, it’s important to get in the habit of testing pH right from the beginning!
Even if the right amounts of nutrients are present, your cannabis plants simply cannot absorb them if the pH isn’t in the correct range.
It’s actually really easy, quick, and cheap to learn how to check and adjust the pH of your water, and there are “pH test kits” specifically made for this purpose.
After you get the hang of it, checking and adjusting the pH and will take you less than 3 minutes each time you water your plants. And your results (monster yields with huge buds and healthy plants) will speak for themselves.
Soil: Maintain 6.0 – 7.0 pH
Hydroponics: Maintain 5.5 – 6.5 pH
Getting the pH exactly right isn’t nearly as important as checking regularly and making sure it stays within these ranges.