Any seasoned cannabis grower understands the importance of monitoring and altering pH for an at-home grow op. But for some reason, pH often flies under the radar for newbie growers who are still trying to figure out the ropes.
This is completely understandable, especially considering the fact that there are tons of moving parts involved for a successful harvest. But that said, no grower should underestimate the power of the perfect pH level for their plants, even those who are brand new to growing.
If you’ve ever taken a basic science class, you probably already know that pH, short for power of hydrogen, is a measurement of how acidic or how basic a solution is. But if your knowledge of pH stops there, you’ve got a long way to go for creating the perfect grow room environment. This guide according to a seasoned ACMPR home grower in Canada can help.
First, Some pH Basics
Understanding the pH scale can be tricky, so let’s start with the basics. According to Elmhurst College, “the pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic.”
Some substances are more basic, like ammonia and lye, while others are more acidic, like vinegar and lemon juice. Pure water has a pH of 0, but this changes as soon are chemicals are mixed in. Just like all living things, cannabis plants thrive at a very specific pH range.
Why Every Grower Needs to Focus on pH
The pH range that most sources claim is ideal for cannabis cultivation is between 6 and 7. The real question is, why? Well, to put things as simple as possible, your plants require a variety of nutrients for healthy growth. When the pH is too high or low, the plants are unable to uptake and process these nutrients to the best of their ability.
There’s actually a very small pH window where plants are able to take up the nutrients they need for proper development – and this window is between 6 and 7. When pH strays outside of this range, cannabis plants can’t get essential macronutrients like nitrogen, potassium, and phosphorous. The same goes for micronutrients like calcium, copper, and magnesium.
No matter how many nutrients you pump into your crop, it doesn’t matter if the pH isn’t right. And most growers know that when plants don’t get the nutrients they need, they experience deficiencies, and sometimes even die off altogether.
So What’s a Grower to Do?
The first step to ensuring healthy pH levels for your grow room is to understand what you’re working with. Every home’s water supply is different based on how the area treats it with chemicals, so your first step is to measure the pH. Quality cannabis PH pens make a difference and allow growers to get exact pH readings.
First-time growers with just a few plants often turn to the cheaper alternative of pH testing strips, but these aren’t nearly as accurate as more high-tech pH pens and meters. The best pH pens will give you exact readings on everything from pH to water temperature to PPM.
The next step is understanding how to alter the pH to create the ideal conditions. There are two liquid solutions available to growers that help with this: pH Up and pH Down. The names of each say it all. One solution is responsible for raising the pH, while the other brings it down.
What About Reverse Osmosis?
Some growers swear by using water that has been through reverse osmosis, a process that removes as much as 99% of dissolved salts from H2O. Other growers, on the other hand, say that this is a waste of time. Regardless of RO debates, there are quite a few perks to using this process (but there are also some drawbacks).
The main advantage of reverse osmosis is for growers who live in an area where the tap water is considered undrinkable. In this case, you wouldn’t want your plants to drink that water. But if you live an area where you can fearlessly chug a glass of water from the tap, RO really isn’t that necessary.
Understand That Hydroponic Growing Is Different
For growers using hydroponic and soilless methods, it’s extremely important to note that pH levels should be slightly lower than with soil growing. Plants that are grown hydroponically prefer the pH to be between a range of 5.5 and 6.5 rather than 6 and 7.
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