So what is pH... and why is measuring it so important?

pH is the measurement of acidity and its opposite, alkalinity in a solution. Neutral pH is 7.0 pH. Acidity measures below seven pH (7.0pH) with alkalinity measuring above it (7.0pH).

It is important to maintain a hydroponic nutrient solution at a pH level where the elements in the nutrient solution are consistently available to the plant. If the solution is too acidic or too alkaline it can cause “lock up” – a situation which restricts certain elements essential for growth from being absorbed by the root structure. This is where things start to go wrong. Deficiencies in the required elements become apparent in the plants growth and can lead to crop death. 

The elements we add to a solution will either increase or decrease the solutions pH measurement. Only accurate measurement of the pH level will allow complete control of the outcome.

What is the preferred pH range for your plants?

Download the optimum nutrient pH range for plants sheet, or have a look at the how pH affects the availability of nutrients to plants chart.


Mastering pH

When the pH is slightly acidic most nutrient elements are available to a plant.

Slightly acidic range:
Hydroponic solutions: between 5.5 pH and 6.3 pH
Soil crops: between 6.2 pH and 7.2 pH

Individual crops have their own preference for pH values. That is, they do best at certain pH levels.

Whatever food solution you use, keep your pH in a fairly tight band. Consistent balance gives consistent growth.

It’s not just the nutrient mix... it’s the right pH that delivers the food.

Click here to view a Cannabis deficiency chart showing issues caused by pH being out of range.