Understanding Soil pH: A Beginner’s Guide

pH. Ugh. It’s one of those finicky things pool owners and chemistry students need to worry about. You probably know that pH levels are indicators of how acidic or basic a substance is but you may not know how it affects the growth and productivity of cannabis. Not to fear! Today we’re discussing the ins and outs of soil pH, and how to ensure your cannabis crop is getting the right soil pH at the right time.

pH: A refresher

For those who have been out of chemistry class for a while, let’s start with the basics. pH, which stands for potential of Hydrogen, is an indicator of how acidic or basic a substance is. pH is measured on a 14-point scale, from zero (the most acidic) to 14 (the most basic). It’s called pH because acidic molecules contain hydrogen, which has the chemical symbol H. At their extremes, both acids and bases are caustic, meaning they react violently with organic tissue, effectively burning or dissolving it. The range of pH found in soil is much more neutral, but vitally important to cannabis production.

Measuring soil pH

Of course, knowing what pH is doesn’t help you if you can’t measure your soil’s acidity. Fortunately, measuring pH is dead easy. Testing kits are available at many retailers for a nominal fee. There are several kinds of commercial testing kits, including treated paper strips, tablets, and electronic sensors. Each comes with instructions on the specifics of its use, but here’s a basic how-to. Simply mix a soil sample from your growing container with enough dechlorinated water (pure water is pH neutral – a 7 on the pH scale) to make wet mud. Insert whichever testing material you’ve purchased. Per the test kit instructions, the testing material will change colour or otherwise indicate the pH. Compare the results to the test kit instructions and you’ll know the pH of your soil.

There’s also a few homemade methods to test for pH, but these are less accurate and not encouraged for ideal cannabis production.

Soil pH for Cannabis growth

Cannabis plants require slightly acidic soil to thrive – pH in the 5.5 to 6.5 range on the scale. What pH does for cannabis is facilitate growth. Maintaining a slightly acidic pH allows cannabis plants to take in nutrients like nitrogen, phosphorus, and potassium, all of which are necessary for growth and flowering of cannabis plants. pH levels within that 5.5-6.5 ‘sweet-spot’ mean that all the fertilization and soil maintenance you do for your plants work to maximum effect. Without proper acidity in the soil, everything else goes to waste.

Correcting Soil pH

Now that we know the importance of soil acidity for cannabis, and how to test for pH in your soil, it’s time to learn how to correct pH. pH can be corrected by, quite simply, adding more acid or base to the soil. However, it’s not quite that easy. While any acid or base will adjust soil pH, many are toxic to plants, animals, and microorganisms. BlueSky’s pH UP and pH DOWN formulas are simply measured and added to your plant’s water before watering. It’s naturally sourced, microorganism friendly, and won’t burn plants the way harsher pH adjusters can. It’s the best choice for cannabis pH management.

Disclaimer: All information provided here is intended to aid in the production of medicinal cannabis and hemp products only. BlueSky does not condone or support the illegal production or consumption of cannabis. All information is provided ‘as is’ and without guarantee. For more information, or to leave comments or concerns, contact our Master Grower at 1-866-866-4330.