Best pH Balance to Grow Marijuana

How Does pH Balance Affect Plant Growth?

There are a variety of factors that affect the way plants grow. From the amount of sunlight and quality of soil to other plants growing nearby, each varying nuance influences the fruits of one’s labor.

Read to learn about how pH balance affects plants, tips to monitor and maintain pH balance, and ways to ensure a more consistent crop:

What’s a Good pH Balance?

Expert horticulturist Jan Chaboya-Hembre of UC Berkeley explains that a soil’s pH balance is measured according to levels of acidity or alkalinity. On a scale from 0 to 14, a pH balance of 7 measures neutral. Acidity levels rank lower than 7, while alkaline levels rank higher than 7.

Not every plant grows at its optimal level in the same pH balance. For instance, blueberries and conifers grow best in more acidic soils with pH balances of 5 – 6.5.

Vegetables and grasses, on the other hand, grow best in only slightly acidic pH balances of 5.8-6.5. Any pH balance above or below the aforementioned values constitute slower growth, as well as nutrient deficiencies.


What about Nutrients?

The nutrients absorbed by plants during their growth are divided into two major categories: macronutrients and micronutrients.

Macronutrients are needed in larger quantities while micronutrients are only needed in small amounts. Macronutrients are further divided into two categories: primary and secondary. Chaboya-Hembre states that most secondary and micronutrient deficiencies can be alleviated by keeping the pH at an “optimum level.”

When a pH level is not ideal, either a shortage of nutrients or a saturation of toxic minerals occur. Chaboya-Hembre explains that soils with a low pH that are highly acidic contain levels of aluminum and manganese, which are toxic to plants. Low-pH-balanced soils, on the other hand, are deficient of nutrients like calcium, magnesium and phosphorous at balances above 6.5.

How Do I Monitor pH Balance?

Now that we’ve established an ideal pH balance for growth, how can you monitor and maintain it? Local San Diego farmer and scholar of sustainable urban agriculture Kevin Bateman says you can test the pH balance of soil using either a home pH kit or test probes.

If you’re interested in going a more sustainable route, you can test the pH balance by boiling a red cabbage and testing the soil in the cabbage water. If the soil turns hot pink, it’s acidic; if it turns green or blue, it’s alkaline. Neutral and ideal pH balances will be shades of purple to magenta.


How Can I Correct pH Balance?

Once the pH balance of soil has been determined, you can balance it out to reach its ideal levels. For soils that are highly alkaline and need to become more acidic, Kevin recommends adding peat moss or decomposed tree matter to the soil to bring down the pH. For soils that are highly acidic, adding limestone and/or wood ash to the soil can increase the pH level. Once the pH level is corrected, plants will be able to get the most out of the soil provided to them.

Are you struggling with the level of nutrients and pH balance in your soil?

We recommend trying a POD! It takes the guess work out of providing the ideal climate for your plants.

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