Hydroponics pH: Why Is It Important?
Hydroponics pH Guide For Optimal Growth
Hydroponics pH levels are of crucial importance for growing healthy plants. Read on to discover how to achieve optimal and stable hydroponics pH levels.
Hydroponics pH: Why Is It Important?
Even with optimal lighting, space, temperature, nutrient availability, and humidity, your plants will not grow well if the growing medium is not in the right pH range.
This is even more important for hydroponic systems, compared to growing in soil.
Hydroponics pH levels are so crucial because it is completely up to the grower to create the ideal growing environment through a water-based nutrient solution. In soil, on the other hand, the interactions of minerals, water, organic matter, and microorganisms help to naturally maintain a relatively stable pH that is conducive to healthy plant growth.
The pH of a solution is a measurement of its acidity or alkalinity on a scale from zero to 14. The midpoint of this scale (7) is pH neutral. As the pH level approaches zero, it becomes increasingly acidic and as it approaches 14 it becomes increasingly alkaline.
For most plants, the ideal hydroponics pH level is slightly acidic, between 5 and 6.5, although many can survive in slightly alkaline conditions.
If the pH of your growing medium is too acidic or too alkaline, then the nutrients will not fully dissolve in the solution and so your plants will not be able to absorb them. This can result in plant nutrient deficiencies that could even lead to death.
Hydroponics pH: How To Test For pH?
For these reasons, it is important to test hydroponics pH levels before you introduce the plants you want to grow.
There are several ways you can do this. The cheapest and simplest method is to use a litmus strip that contains dyes extracted from lichens. These change colour when dipped in the water-based nutrient solution. You can then determine the pH level against a provided colour comparison chart.
While straightforward to use, litmus strips are not the most accurate method for working out pH levels. A similar but more precise approach is a liquid pH test kit. With these, you drip a small amount of the solution in a vial and the resulting reading tends to be more reliable since they're designed especially for testing hydroponics pH levels.
However, the most popular method nowadays is a digi pH pen. Simply dip one end into the nutrient solution and the pH will appear on a screen. While more accurate, digi pH pens need to be calibrated and cleaned regularly for best results.
Another more expensive option is to use an automatic pH metre which provides continuous monitoring of pH levels, as well as providing various other features such as data logging and temperature readings.
It is a good idea to test hydroponics pH levels regularly as the solution tends to become more alkaline as plants absorb nutrients.
How To Adjust Hydroponics pH Levels
The best way to lower the pH level of your nutrient solution is to use small quantities of a pH- product specially formulated for hydroponics. To increase the pH level, use a pH+ product.
After adding either solution, check the nutrient solution's pH levels again.
Alternatively, you could add white vinegar or citric acid to reduce pH and baking soda to increase pH, but these can be imprecise and should only be relied on as a short-term solution.
Hydroponics pH: Key Takeaways
- Plants need a growing environment that lies within a particular pH range.
- This is especially important for plants grown in hydroponic systems as there is no soil to help regulate pH levels.
- To test hydroponics pH levels, there are several easy-to-use options available.
- To adjust pH levels to the optimal range for your plants, use a pH- or pH+ solution.