What is pH?

„Potentia hydrogenii“ or pH is the logarithmic scale for measuring the acidity or alkalinity of a solution. What pH means to scientists is similar to the gardener's interpretation. However, differences arise in the application of this understanding.
In the laboratory, pH is used to quantify the ratio of negatively and positively charged ions in a liquid. While in growth the pH level is important when it comes to watering and nourishing plants. In addition, it is essential to monitor the pH of the growth medium and adjust it as needed.

The pH scale varies from 0-14, going from acid to base. PH 7 is considered a neutral value. Just like the Richter scale used to measure earthquakes, the pH scale is multiplied by each point by a factor of 10, i.e. pH 9.0 is ten times more alkaline than 8.0.

What is the EC?

This abbreviation means electrical conductivity. For gardeners, and especially for people who grow in hydroponics, EC measurement is essential for the proper application of nutrients. In the laboratory, the EC measures the electrical potential of materials. In contrast, the only material and liquid that the gardener is interested in is the growing environment and water. By measuring EC, we can understand how many nutrients are in the solution, thus not only applying the optimal values, but also avoiding Nutrient lockout after over-fertilizing.

Optimal values

The optimal pH and EC values ​​for plants growing depend on three factors - the growing substrate, nutrients and water. For soil, pH of 6.0-6.5 is perfect.
While hydroponic and coco producers should strive for 5.8 pH or at least maintain a pH of around 5.5-6.1. The soil is a more forgiving environment and acts as a buffer for the root zone. In contrast, hydraulic systems are far less forgiving and pH levels must be perfect at all times.
The perfect EU value is different for each plant and plant variety. Some species need heavy feeding, the preference is for higher EC values ​​of 2.5+, while others can grow around 1.0 EC.
The water has an EC value of 0 and is usually pH neutral, around 7.0. Specialized soil is usually around 6.0 pH and hydro clay and perlite stones are neutral sterile media. 

Hydroponics obviously requires more fine-tuning than low-maintenance organic tillage. Rockwool cubes should be pre-soaked in 5.8pH solution before planting seeds or cuttings in them.
The scale below gives approximate EC values ​​for a 10-week life cycle.

A few important points

  • The experienced gardener is careful when monitoring nutrient doses and measures the pH and EC values ​​of each meal. PH and EC fluctuations should be avoided.
  • The pH value of the water should be constant and the EC should increase gradually, according to the size and behavior of the plants. The water should also be changed weekly to avoid salt buildup, this is very important for hydropower producers.
  • EC measurement is the most accurate reading of nutrients in nutrient solutions and culture medium.

pH and EC meters

The full set of meters we offer can be found here. If you are a beginner or just do not want to exceed your budget, we recommend the pH and EC testers of ADWA. If you want to save the effort of measuring pH levels every time, the monitor is made for you.


Otherwise, you can turn to Bluelab products. They have great products from pH and EC testers for solutions and soils to monitors.

*** IMPORTANT *** Never allow the tester electrode to dry. Not only does this reduce it's life, but there is a good chance that it will stop working. Always keep the electrode tip in storage liquid. *** IMPORTANT ***

After several uses, the testers stop reading accurately, so calibration tools are used. There are two types: The first is a disposable powder that dissolves in water. The second is an already calibrated solution that is sold in a bottle. The full range of calibration products can be found here.