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PH Levels And Why They Matter

Let’s clear up why pH is important to Cannabis

What The pH?

Before we go anywhere, let’s just make sure you know what pH is. Discovered by Danish chemist S. P. L. Sørensen… oh right, no need to discuss this so in-depth!

Right, so pH is the scale, between 0 -14, used to specify how acidic or alkaline a substance is. Purified water (tap water can vary for a number of reasons) is neutral at 7, liquid drain cleaner is the most alkaline at 14 and hydrochloric acid is the most acidic at 0.

When it comes to your cannabis plant, these levels matter. Imagine if your soil is at a pH of hydrochloric acid, not only should you consider moving away from your home, but your marijuana would be melting. Anyway, we’re getting distracted writing this blog. The right level ensures that the nutrients in the substrate are healthy. The correct pH means that your plant can easily access the right stuff.

In cannabis’s natural habitat, the soil is normally slightly acidic, thus your homegrown should be as well. But not everyone grows their crop in soil, some do it hydroponically or in another substrate.

Anyway, let’s dive into substrate and pH levels.

Cannabis Soil pH

The optimal pH level for your soil in the root zone is between 6.0 and 7.0. As we said before, your weed likes a little ACID!

Happy, thriving Cannabis plants have a pH level between 6 & 7

Before you go acid crazy, there’s no perfect zone, so if you do get a reading of 6.2 you don’t need to go and grab your Flora Tripack just yet. Though it does contain a pH measuring kit, so ignore me, grab one, and get testing. As a medium, soil is very forgiving and pH levels can be adjusted with a simple watering.

If it is above or below these zones, the micro-organisms will start dying off, and the plant will start to wilt. Which isn’t good. The Flora Tripack has pH uppers and downers, you will need to read the instructions carefully on the pack about how to apply, which is normally: mix substance and pour onto soil. There are loads of “organic” methods of adjusting pH, but honestly, we don’t have enough space on the page to discuss this.

YES, you can add vinegar to make the soil more acidic, but you should maybe only use the grape, as white vinegar can be used as a natural bleach – WE GET IT! JUST USE THE STORE BOUGHT STUFF THAT SCIENTISTS HAVE MADE! #DiscussionOver

But honestly, if you are using Freedom Farm Organic Classic Craft Soil you should be fine.

Soilless Cannabis pH

Now, with hydroponic setups or grows just utilising coco, things change a lot. Now your optimal pH level at the root zone is lower and should be 5.5 and 6.5.

ph scale for hydroponics
With hydroponic setups or grows just utilising coco, your optimal pH level at the root zone is lower and should be 5.5 and 6.5.

As with soil, the levels can fluctuate across the range. If you must know, calcium is mostly absorbed at pH levels above 6, and manganese is usually absorbed at levels slightly below that.

But unlike soil, you can easily swing pH levels wildly. As the substrate is neutral there are no organic and natural ways of slowing down the process. So, if you’re spilling your lemon juice all over the place, your plants are in for a bad sour trip.

Also, you need to be very careful when administering nutrients as pH levels can go wild. If you have chosen this route, we’re sure you’re are tinkering with your units already. In fact, if you’re a “hydro person” reading this article, you are probably playing with the pH levels right now.

And again, we strongly suggest using the pH uppers and downers provided in the Flora Tripack, as it has been formulated, and you can follow the instructions laid out by scientists. Then again, if you need to be that person wailing about the organic method, if the pH is too high, add water, and if it is too low, add some baking soda.

How much should you add? We can’t tell you, as WE’RE NOT IN THE ROOM! That’s the issue with going fully into the alternative methods, we can’t guarantee results, so it’ll be up to you to experiment.

So, there we go. We spoke about pH levels. If you still want to chat about this more, visit us in our store at the Mason’s Press, 1 Ravenscraig Road, Woodstock.

Zootly says: “For a cannabis outlet, this article spoke a lot about acid…”

Words By: Andrew Macfarlane, writer and budding horticulturist.

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